Pharmacotherapeutics for Advanced Practice
A PRACTICAL APPROACH FOURTH EDITION
Pharmacotherapeutics for Advanced Practice
A PRACTICAL APPROACH FOURTH EDITION
E D I T O R S
Virginia P. Arcangelo, PhD, NP Family Nurse Practitioner, Retired
Berlin, New Jersey
Andrew M. Peterson, PharmD, PhD, FCPP John Wyeth Dean
Professor of Clinical Pharmacy and Professor of Health Policy University of the Sciences in Philadelphia
Veronica F. Wilbur, PhD, APRN-FNP, CNE, FAANP Assistant Professor of Graduate Nursing
West Chester University West Chester, Pennsylvania
Jennifer A. Reinhold, BA, PharmD, BCPS, BCPP Associate Professor of Clinical Pharmacy
Philadelphia College of Pharmacy University of the Sciences in Philadelphia
Executive Editor: Shannon W. Magee Product Development Editor: Maria M. McAvey Developmental Editor: Tom Conville Senior Marketing Manager: Mark Wiragh Production Project Manager: Marian Bellus Design Coordinator: Elaine Kasmer Manufacturing Coordinator: Kathleen Brown Prepress Vendor: SPi Global
Copyright © 2017 Wolters Kluwer
Copyright © 2005 (2nd edition) Lippincott Williams & Wilkins, 2011 (3rd edition) Lippincott Williams & Wilkins.
All rights reserved. This book is protected by copyright. No part of this book may be reproduced or transmitted in any form or by any means, including as photocopies or scanned-in or other electronic copies, or utilized by any information storage and retrieval system without written permission from the copyright owner, except for brief quotations embodied in critical articles and reviews. Materials appearing in this book prepared by individuals as part of their official duties as U.S. government employees are not covered by the above-mentioned copyright. To request permission, please contact Wolters Kluwer at Two Commerce Square, 2001 Market Street, Philadelphia, PA 19103, via email at email@example.com, or via our website at lww.com (products and services).
9 8 7 6 5 4 3 2 1
Printed in China
Library of Congress Cataloging-in-Publication Data Names: Arcangelo, Virginia P, editor. | Peterson, Andrew M., editor. | Wilbur, Veronica, editor. | Reinhold, Jennifer A., editor. Title: Pharmacotherapeutics for advanced practice : a practical approach / editors, Virginia P. Arcangelo, Andrew M. Peterson, Veronica F. Wilbur, Jennifer A. Reinhold. Description: Fourth edition. | Philadelphia : Wolters Kluwer,  Identifiers: LCCN 2016002801 | ISBN 9781496319968 Subjects: | MESH: Drug Therapy—methods | Pharmaceutical Preparations—administration & dosage Classification: LCC RM262 | NLM WB 330 | DDC 615.5/8—dc23 LC record available at http://lccn.loc.gov/2016002801
This work is provided “as is,” and the publisher disclaims any and all warranties, express or implied, including any warranties as to accuracy, comprehensiveness, or currency of the content of this work.
This work is no substitute for individual patient assessment based upon healthcare professionals’ examination of each patient and consideration of, among other things, age, weight, gender, current or prior medical conditions, medication history, laboratory data and other factors unique to the patient. The publisher does not provide medical advice or guidance and this work is merely a reference tool. Healthcare professionals, and not the publisher, are solely responsible for the use of this work including all medical judgments and for any resulting diagnosis and treatments.
Given continuous, rapid advances in medical science and health information, independent professional verification of medical diagnoses, indications, appropriate pharmaceutical selections and dosages, and treatment options should be made and healthcare professionals should consult a variety of sources. When prescribing medication, healthcare professionals
are advised to consult the product information sheet (the manufacturer’s package insert) accompanying each drug to verify, among other things, conditions of use, warnings and side effects and identify any changes in dosage schedule or contraindications, particularly if the medication to be administered is new, infrequently used or has a narrow therapeutic range. To the maximum extent permitted under applicable law, no responsibility is assumed by the publisher for any injury and/or damage to persons or property, as a matter of products liability, negligence law or otherwise, or from any reference to or use by any person of this work. LWW.com
We dedicate this book to all our students. This book never would have come to fruition without
the impact of the students who have touched our lives. It is our hope that this book and its evolution into the fourth edition has influenced more than just our students but that it has
helped to promote excellence in patient care through all of its users.
Virginia P. Arcangelo, PhD, NP Family Nurse Practitioner, Retired Berlin, New Jersey
Laura Aykroyd, PharmD Clinical Pharmacy Specialist–Neurocritical Care Department of Pharmacy IU Health Methodist Hospital Indianapolis, Indiana
Kelly Barranger, MSN, RN, CRNP Certified Registered Nurse Practitioner Department of Nursing Veterans Affairs Philadelphia, Pennsylvania
John Barron, PharmD Staff Vice President and Clinical Research Advisor HealthCore, Inc. Wilmington, Delaware
Laura L. Bio, PharmD, BCPS Assistant Professor Department of Pharmacy Practice Philadelphia College of Pharmacy Philadelphia, Pennsylvania Clinical Pharmacist Department of Pharmacy Children’s Regional Hospital at Cooper University Hospital Camden, New Jersey
Lauren M. Czosnowski, PharmD, BCPS Assistant Professor Department of Pharmacy Practice Butler University Clinical Specialist Pharmacy Department IU Health Methodist Hospital Indianapolis, Indiana
Quinn A. Czosnowski, PharmD Clinical Pharmacy Specialist Pharmacy Department
IU Health Methodist Hospital Indianapolis, Indiana
David Dinh, PharmD, BCPS Clinical Pharmacy Specialist, Emergency Medicine Department of Pharmacy Yale New Haven Hospital New Haven, Connecticut
Amy M. Egras, PharmD, BCPS, BC-ADM Associate Professor Department of Pharmacy Practice Jefferson School of Pharmacy Clinical Pharmacist Jefferson Family Medicine Associates Thomas Jefferson University Philadelphia, Pennsylvania
Kelleen N. Flaherty, MS Adjunct Assistant Professor Department of Biomedical Writing University of the Sciences in Philadelphia Philadelphia, Pennsylvania
Maria C. Foy, PharmD, BCPS, CPE Clinical Specialist, Palliative Care Pharmacy Department Abington Memorial Hospital Abington, Pennsylvania
Steven P. Gelone, PharmD Chief Development Officer Nabriva Therapeutics King of Prussia, Pennsylvania
Andrew J. Grimone, PharmD, BCPS-AQ ID Assistant Professor Department of Nursing Clarion University of Pennsylvania Clarion, Pennsylvania Clinical Pharmacy Manager Department of Pharmacy Saint Vincent Hospital Allegheny Health Network Erie, Pennsylvania
Anisha B. Grover, PharmD, BCACP Assistant Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration
Philadelphia College of Pharmacy University of the Sciences Philadelphia, Pennsylvania
Diane E. Hadley, PharmD, BCACP Assistant Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration University of the Sciences Philadelphia, Pennsylvania
Emily R. Hajjar, PharmD, BCPS, BCACP, CGP Associate Professor Department of Pharmacy Practice Jefferson School of Pharmacy Philadelphia, Pennsylvania
Amalia M. Issa, PhD, MPH, FCPP Professor of Health Policy Department of Health Policy and Public Health Director Program in Personalized Medicine and Targeted Therapeutics University of the Sciences Philadelphia, Pennsylvania
Tep Kang, PharmD, BCPS Adjunct Instructor Department of Nursing University of Delaware Newark, Delaware Wilmington University New Castle, Delaware Critical Care Pharmacist Department of Pharmacy Christiana Care Health Services Newark, Delaware
Alice Lim, PharmD, BCACP Assistant Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration Philadelphia College of Pharmacy Philadelphia, Pennsylvania
Laura A. Mandos, BS, PharmD, BCPP Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration Philadelphia College of Pharmacy University of the Sciences Philadelphia, Pennsylvania
Lauren K. McCluggage, PharmD Associate Professor Lipscomb University College of Pharmacy Clinical Pharmacist Department of Pharmacy St. Thomas West Hospital Nashville, Tennessee
Karleen Melody, PharmD, BCACP Assistant Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration Philadelphia College of Pharmacy University of the Sciences Philadelphia, Pennsylvania
Isabelle Mercier, PhD Associate Professor Pharmaceutical Sciences University of the Sciences Philadelphia, Pennsylvania
Carol Gullo Mest, PhD, RN, ANP-BC Professor of Nursing Director of Graduate Program DeSales University Center Valley, Pennsylvania
Samir K. Mistry, PharmD Senior Director Specialty Product Strategy CVS Health Minneapolis, Minnesota
Lorraine Nowakowski-Grier, MSN, APRN, BC, CDE Adjunct Faculty Department of Nursing College of Health Professions Wilmington University New Castle, Delaware Nurse Practitioner, Diabetes Educator Department of Nursing Education and Development Christiana Care Health Services Newark, Delaware
Judith A. O’Donnell, MD Associate Professor of Medicine Division of Infectious Diseases Perelman School of Medicine at the University of Pennsylvania Chief, Division of Infectious Diseases
Hospital Epidemiologist and Director, Infection Prevention & Control Penn Presbyterian Medical Center Philadelphia, Pennsylvania
Staci Pacetti, PharmD Assistant Professor Department of Nursing Rutgers University School of Nursing Camden, New Jersey
Andrew M. Peterson, PharmD, PhD, FCPP John Wyeth Dean Professor of Clinical Pharmacy and Professor of Health Policy University of the Sciences in Philadelphia Philadelphia, Pennsylvania
Louis R. Petrone, MD Clinical Assistant Professor Family and Community Medicine Sidney Kimmel Medical College Attending Physician Family and Community Medicine Thomas Jefferson University Hospital Philadelphia, Pennsylvania
Melody D. Randle, DNP, FNP-C, MSN, CCNS, CNE Chair Nurse Practitioner Program College of Health Professions Wilmington University New Castle, Delaware
Troy L. Randle, DO, FACC, FACOI Assistant Program Director of Cardiology Department of Cardiology School of Osteopathic Medicine Rowan University Cardiologist Lourdes Cardiology Cherry Hill, New Jersey
Jennifer A. Reinhold, BA, PharmD, BCPS, BCPP Associate Professor of Clinical Pharmacy Philadelphia College of Pharmacy University of the Sciences in Philadelphia Philadelphia, Pennsylvania
Christopher C. Roe, MSN, ACNP-BC Nurse Practitioner Manager
Center for Heart and Vascular Health Christiana Care Health Systems Newark, Delaware
Cynthia A. Sanoski, PharmD, BCPS, FCCP Department Chair and Associate Professor Department of Pharmacy Practice Jefferson School of Pharmacy Thomas Jefferson University Philadelphia, Pennsylvania
Briana L. Santaniello, MBA, PharmD PGY1 Managed Care Pharmacy Resident University of Massachusetts Medical School’s Clinical Pharmacy Services Shrewsbury, Massachusetts
Jason J. Schafer, PharmD, MPH Associate Professor Department of Pharmacy Practice Jefferson School of Pharmacy Thomas Jefferson University Philadelphia, Pennsylvania
Shelly Schneider, APN Nurse Practitioner Woodbury Dermatology Woodbury, New Jersey
Jean M. Scholtz, BS, PharmD, BCPS, FASHP Associate Professor, Vice Chair Department of Pharmacy Practice Philadelphia College of Pharmacy Philadelphia, Pennsylvania
Anita Siu, PharmD Clinical Associate Professor Department of Pharmacy Practice and Pharmacy Administration Rutgers, The State University of New Jersey Piscataway, New Jersey Neonatal/Pediatric Pharmacotherapy Specialist Department of Pharmacy Jersey Shore University Medical Center Neptune, New Jersey
Sarah A. Spinler, PharmD Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration Philadelphia College of Pharmacy University of the Sciences
Joshua J. Spooner, PharmD, MS Associate Professor of Pharmacy College of Pharmacy Western New England University Springfield, Massachusetts
Linda M. Spooner, PharmD, BCPS, FASHP Professor of Pharmacy Practice Department of Pharmacy Practice MCPHS University School of Pharmacy–Worcester/Manchester Clinical Pharmacy Specialist in Infectious Diseases Saint Vincent Hospital Worcester, Massachusetts
Richard G. Stefanacci, DO, MGH, MBA, AGSF, CMD Faculty School of Population Health Thomas Jefferson University Philadelphia, Pennsylvania Chief Medical Officer The Access Group Berkeley Heights, New Jersey Senior Physician Mercy LIFE Trinity Health System Philadelphia, Pennsylvania
James C. Thigpen Jr, PharmD, BCPS Associate Professor Department of Pharmacy Practice Bill Gatton College of Pharmacy East Tennessee State University Johnson City, Tennessee
Tyan F. Thomas, PharmD Associate Professor of Clinical Pharmacy Department of Pharmacy Practice and Pharmacy Administration Philadelphia College of Pharmacy at the University of the Sciences Clinical Pharmacy Specialist Department of Pharmacy Philadelphia VA Medical Center Philadelphia, Pennsylvania
Karen J Tietze. , PharmD Professor of Clinical Pharmacy Philadelphia College of Pharmacy University of the Sciences in Philadelphia Philadelphia, Pennsylvania
Elena M. Umland, PharmD Associate Dean, Academic Affairs Professor, Pharmacy Practice Jefferson School of Pharmacy Thomas Jefferson University Philadelphia, Pennsylvania
Sarah F. Uroza, PharmD Assistant Professor Department of Pharmacy Practice Lipscomb University Clinical Pharmacist Faith Family Medical Clinic Nashville, Tennessee
Craig B. Whitman, PharmD, BCPSClinical Associate Professor of Pharmacy Practice Temple University School of Pharmacy Clinical Specialist, Critical Care Temple University Hospital Philadelphia, Pennsylvania
Veronica F. Wilbur, PhD, APRN-FNP, CNE, FAANP Assistant Professor of Graduate Nursing West Chester University West Chester, Pennsylvania
Vincent J. Willey, PharmD Staff Vice President, Industry Sponsored Research HealthCore, Inc. Wilmington, Delaware
Eric T. Wittbrodt, PharmD, MPH Director, Health Economics and Outcomes Research at AstraZeneca
PREVIOUS EDITION CONTRIBUTORS
Angela A. Allerman, PharmD, BCPS
Kelly Barranger, MSN, RN, CRNP
John Barron, BS Pharmacy, PharmD
Laura L. Bio, PharmD, BCPS
Tim A. Briscoe, PharmD, CDE
Debra Carroll, MSN, CRNP
Quinn A. Czosnowski, PharmD, BCPS
Lauren M. Czosnowski, PharmD, BCPS
Elyse L. Dishler, MD
Amy M. Egras, PharmD, BCPS
Heather E. Fean, MSN, APN-C
Kelleen N. Flaherty, MS
Maria C. Foy, PharmD, CPE
Stephanie A. Gaber, PharmD, CDE
Jomy M. George, PharmD, BCPS
Ellen Boxer Goldfarb, CRNP
Andrew J. Grimone, PharmD, RPh, BCPS
Emily R. Hajjar, PharmD, BCPS, CGP
Andrea M. Heise, MSN, APN-C
Lauren K. McCluggage, PharmD, BCPS
Carol Gullo Mest, PhD, RN, ANP-BC
Samir K. Mistry, PharmD
Angela Cafiero Moroney, PharmD
Betty E. Naimoli, MSN, CRNP
Jessica O’Hara, PharmD
Dharmi Patel, PharmD
Jeegisha R. Patel, PharmD
Louis R. Petrone, MD
Jennifer A. Reinhold, BA, PharmD, BCPS
Alicia M. Reese, PharmD, MS, BCPS
Cynthia A. Sanoski, BS, PharmD, BCPS, FCCP
Matthew Sarnes, PharmD
Jason J. Schafer, PharmD, BCPS, AAHIVE
Susan M. Schrand, MSN, CRNP
Henry M. Schwartz, BSc Pharm, PharmD, CDE
Anita Siu, PharmD
Joshua J. Spooner, PharmD, MS
Linda M. Spooner, PharmD, BCPS
Liza Takiya, PharmD, BCPS
Jim Thigpen, PharmD, BCPS
Tyan F. Thomas, PharmD, BCPS
Craig B. Whitman, PharmD, BCPS
Veronica F. Wilbur, PhD, FNP-BC
Eric T. Wittbrodt, PharmD
Pharmacotherapeutics for Advanced Practice originated from our combined experience in teaching nurse practitioners and in practice in primary care. As a nurse practitioner and educator herself, Virginia saw a need for practical exposure to the general principles of prescribing and monitoring drug therapy, particularly in the Family Practice arena. As a PharmD, Andrew saw a need to be able to teach new prescribers how to think about prescribing systematically, regardless of the disease state. For this edition, we have expanded the editorial staff to include Veronica F. Wilbur and Jennifer Reinhold. Veronica, a Family Nurse Practitioner and PhD in Nursing, has extensive experience in education of Advanced Practice Nurses and primary care practice. Jennifer, a PharmD, has expertise in pharmacotherapy and prescribing in primary care. Both of these colleagues were contributors in previous editions and understand the focus, intent, and direction of this text.
This edition still provides basic pharmacology, while also providing a process and framework through which learners can begin to think pharmacotherapeutically. The text still allows learners to identify a disease, review the drugs used to treat the disease, select treatment based on goals of therapy and special patient considerations, and adjust therapy if it fails to meet goals.
This text meets the needs of both students and practitioners in a practical approach that is user friendly. It teaches the practitioner how to prescribe and manage drug therapy in primary care. The book has evolved over the years, based on input from students, academicians, and practitioners. Long-standing contributors were asked to update their chapters, and new contributors were selected based on their academic or practice expertise to provide a combination of evidence-based medicine and practical experience. The text considers disease- and patient-specific information. With each chapter, there are tables and evidence-based algorithms that are practical and easy to read and that complement the text.
Additionally, the text guides the practitioner to a choice of second- and third-line therapy when the first line of therapy fails. Since new drugs are being marketed continually, drug classes are discussed with a focus on how the broader, class-specific properties can be applied to new drugs. Each chapter ends with a simple case study or series of questions designed to prompt the learner to think systematically and the teacher to ask critical questions. Also, the disorder chapter’s case study asks the same questions; reinforcing a clinical decision-making process and promoting critical thinking skills. There are no answers to the questions in the text since the authors believe that the purpose of the case studies is to promote discussion and that there may be more than one correct answer to each question, especially as new drugs are developed. However, one potential answer to each question in the case is available online for use by faculty. Additionally, there is an
additional case with several sample multiple-choice questions for each chapter online. We realize that there may be several answers to these questions and the authors have just provided one option. To assist faculty in the classroom, there are power point slides available online for each chapter. To assist the student, the acronyms contained in each chapter are defined in a separate file online as well.
ORGANIZATION OF THE BOOK
Unit 1—Principles of Therapeutics As with previous editions, the Principles Unit of the book reviews basic elements of therapeutics necessary for safe and effective prescribing. The first chapter introduces the prescribing process, including how to avoid medication errors. The next two chapters provide the foundation of therapeutics, including information on the pharmacokinetics and pharmacodynamics of drugs and drug–drug/drug–food interactions. The following three chapters review how these foundations change in pediatric, pregnant, and geriatric patients. Similarly, the basics of the principles of pain management and infectious disease therapy are reviewed in the next two chapters so that the reader can learn how these concepts are applied to the disorders discussed in the following units. Updated Complementary and Alternative Medicine (CAM) and Pharmacogenomics chapters are included in this unit, recognizing the growing use of these modalities in all aspects of patient care.
Units 2 through 12—Disorders This section of the book, consisting of 41 chapters, reviews commonly seen disorders in the primary care setting. Although not all-inclusive, the array of disorders allows the reader to gain an understanding of how to approach the pharmacotherapeutic treatment of any disorder. The chapters are designed to give a brief overview of the disease process, including the causes and pathophysiology, with an emphasis placed on how drug therapy can alter the pathologic state. Diagnostic Criteria and Goals of Therapy are discussed and underlie the basic principles of treating patients with drugs. Osteoarthritis and rheumatoid arthritis have been split and each has a chapter devoted to it. A new chapter on Parkinson Disease has been added since this is frequently treated in primary care. Each chapter has been updated with the newest therapies available at the time of writing.
The drug sections review the agents’ uses, mechanism of action, contraindications and drug interactions, adverse effects, and monitoring parameters. This discussion is organized primarily by drug class, with notation to specific drugs within the text and the tables. The tables provide the reader with quick access to generic and trade names and dosages, adverse events, contraindications, and special considerations. Used together, the text and tables provide the reader with sufficient information to begin to choose drug therapy.
The section on Selecting the Most Appropriate Agent aids the reader in deciding which drug to choose for a given patient. This section contains information on first-line, second-line, and third-line therapies, with rationales for why drugs are classified in these categories. Accompanying this section is an algorithm outlining the thought process by which clinicians select an initial drug therapy. Again, the text organization and the illustrative algorithms provide readers with a means of thinking through the process of
selecting drugs for patients. In the third edition, we have kept the Recommended Order of Treatment tables and updated them, along with the algorithms and drug tables, to reflect current knowledge. Each chapter has been updated to reflect the most current guidelines available at the time of writing. However, medicine and pharmacotherapy are constantly changing, and it remains the clinician’s responsibility to identify the most current information.
Included in each chapter is a section on Monitoring Patient Response. This encompasses clinical and laboratory parameters, times when these items should be monitored, and actions to take in case the parameters do not meet the specified goals of therapy. In addition, special patient populations are discussed when appropriate. These discussions include pediatric and geriatric patients but may also include ethnic- or sex- related considerations. Last, this section includes a discussion of patient education material relevant to the disease and drugs chosen. In each chapter, there is a patient education section that includes information on CAM related to that disorder as well as sections on external information for patients and practitioners.
Each of the case studies has been reviewed and updated as appropriate. However, the pedagogical style of reasoning remains the same. As previously stated, answers to these case studies are not supplied since the purpose is to promote discussion and evoke a thought process. Also, as time changes, so do therapies. The cases are short, compelling the learner to ask questions about the patient and allowing flexibility for multiple correct answers to be developed by the instructor as they work through the clinical decision-making process.
Units 13 and 14—Pharmacotherapy in Health Promotion and Women’s Health These units discuss several areas of interest for promoting health or maintaining a healthy lifestyle using medications, including smoking cessation, immunizations, and weight management; the chapter on travel medicine has been eliminated since there are specialty clinics that provide this service, and it is not done frequently in primary care. The four chapters in Women’s Health assist the learner to recognize the special nature of care that this population deserves.
Unit 15—Integrative Approach to Patient Care While there are only two chapters in this unit, they represent the culmination of the text. Practitioners need to have an understanding of the economics of pharmacotherapeutics in order to effectively prescribe medications and treat patients. This chapter is updated with information on the Affordable Care Act and its impact on therapeutic decision making while still being anchored in the basics of pharmacoeconomics, formulary decision making, co-pays, prior authorizations, and Medicare as well as managed care as it applies to prescribing medications.
The last chapter, Integrative Approaches to Pharmacotherapy, is an attempt to examine
real-life, complex cases. Each case addresses the nine questions posed in the individual chapter case studies, but now provides the reader with examples of how to approach the case studies and examines issues to consider when presented with more than one diagnosis. These cases are more complex, requiring the reader to think through multiple diseases and therapies instead of a single disorder in isolation. Within this chapter, we do offer potential answers to the cases. These may not be the only answers but indicate some of the thought processes that go into the decision-making process in the pharmacologic management of a problem.
Chapter Organization This edition continues the consistent format approach throughout each disorder chapter. Each chapter begins with the background and pathophysiology of the disorder, followed by a discussion of the relevant classes of drugs. These broad categories are then integrated in the section on Selecting the Most Appropriate Agent.
Drug Overview Tables are also organized consistently, giving the reader much information on each drug, including the usual dose, contraindications and side effects, and any special considerations a prescriber should be aware of during therapy. Algorithms provide the reader with a visual cue on how to approach treating a patient.
Recommended Order of Treatment tables provide the reader with basic drug therapy selection, from first-line to third-line therapies for each disorder. These, coupled with the algorithms and the drug tables, are the core of the text.
A Case Study is provided for each disorder discussed. These short cases are designed to stimulate discussion among students and with instructors. The nine questions at the end of each case are tailored to each disorder but remain similar across all cases to reinforce the process of thinking pharmacotherapeutically.
Pharmacotherapeutics for Advanced Practice continues to provide primary care students with a reasoned approach to learning pharmacotherapeutics and to serve as a reference for the seasoned practitioner. Prescribing is becoming more and more complex, and the information in this book has helped us in our own practices. As experienced educators and practitioners, we are dedicated to providing you with a textbook that will meet your needs.
Virginia P. Arcangelo Andrew M. Peterson Veronica F. Wilbur
Jennifer A. Reinhold
We would like to thank Shannon Magee, Maria McAvey, and Marian Bellus, from Wolters Kluwer/Lippincott Williams & Wilkins and Tom Conville, Development Editor, for all their invaluable assistance. We are also forever indebted to the contributors who spent countless hours on this project. Without them, this would never have become a reality.
In addition, we would like to thank our families who supported us throughout the project and understand the importance of this book to us.
Contributors Previous Edition Contributors Preface Acknowledgments
UNIT 1 Principles of Therapeutics 1 Issues for the Practitioner in Drug Therapy
Virginia P. Arcangelo & Veronica F. Wilbur
2 Pharmacokinetic Basis of Therapeutics and Pharmacodynamic Principles Andrew M. Peterson
3 Impact of Drug Interactions and Adverse Events on Therapeutics Tep Kang & Andrew M. Peterson
4 Principles of Pharmacotherapy in Pediatrics Anita Siu & James C. Thigpen Jr
5 Principles of Pharmacotherapy in Pregnancy and Lactation Andrew M. Peterson & Lauren M. Czosnowski
6 Pharmacotherapy Principles in Older Adults Richard G. Stefanacci
7 Principles of Pharmacology in Pain Management Maria C. Foy
8 Principles of Antimicrobial Therapy Steven P. Gelone, Staci Pacetti, & Judith A. O’Donnell
9 Complementary and Alternative Medicine Virginia P. Arcangelo
10 Pharmacogenomics Isabelle Mercier, Andrew M. Peterson, & Amalia M. Issa
UNIT 2 Pharmacotherapy for Skin Disorders 11 Contact Dermatitis
Virginia P. Arcangelo
12 Fungal Infections of the Skin
Virginia P. Arcangelo
13 Viral Infections of the Skin Virginia P. Arcangelo
14 Bacterial Infections of the Skin Jason J. Schafer & Maria C. Foy
15 Psoriasis Shelly Schneider
16 Acne Vulgaris and Rosacea Virginia P. Arcangelo
UNIT 3 Pharmacotherapy for Eye and Ear Disorders 17 Ophthalmic Disorders
Joshua J. Spooner
18 Otitis Media and Otitis Externa Laura L. Bio
UNIT 4 Pharmacotherapy for Cardiovascular Disorders 19 Hypertension
Kelly Barranger & Diane E. Hadley
20 Hyperlipidemia John Barron & Vincent J. Willey
21 Chronic Stable Angina Andrew M. Peterson & Christopher C. Roe
22 Heart Failure Andrew M. Peterson, Melody D. Randle, & Troy L. Randle
23 Arrhythmias Cynthia A. Sanoski & Andrew M. Peterson
UNIT 5 Pharmacotherapy for Respiratory Disorders 24 Upper Respiratory Infections
Karleen Melody & Anisha B. Grover
25 Asthma Karen J. Tietze
26 Chronic Obstructive Pulmonary Disease Karen J. Tietze
27 Bronchitis and Pneumonia Andrew J. Grimone, Virginia P. Arcangelo, & Eric T. Wittbrodt
UNIT 6 Pharmacotherapy for Gastrointestinal Tract Disorders427 28 Nausea and Vomiting
Virginia P. Arcangelo & Veronica F. Wilbur
29 Gastroesophageal Reflux Disease and Peptic Ulcer Disease Alice Lim
30 Constipation, Diarrhea, and Irritable Bowel Syndrome Veronica F. Wilbur
31 Inflammatory Bowel Disease David Dinh
UNIT 7 Pharmacotherapy for Genitourinary Tract Disorders 32 Urinary Tract Infection
Virginia P. Arcangelo
33 Prostatic Disorders and Erectile Dysfunction Virginia P. Arcangelo
34 Overactive Bladder Jennifer A. Reinhold
35 Sexually Transmitted Infections Virginia P. Arcangelo
UNIT 8 Pharmacotherapy for Musculoskeletal Disorders 36 Osteoarthritis and Gout
Sarah F. Uroza, Lauren K. McCluggage, & Carol Gullo Mest
37 Rheumatoid Arthritis Lauren K. McCluggage & Carol Gullo Mest
UNIT 9 Pharmacology for Neurological/Psychological Disorders 38 Headaches
Kelleen N. Flaherty
39 Seizure Disorders Quinn A. Czosnowski, Craig B. Whitman, & Laura Aykroyd
40 Major Depressive Disorder Jennifer A. Reinhold
41 Anxiety Disorders Laura A. Mandos & Jennifer A. Reinhold
42 Insomnia and Sleep Disorders Veronica F. Wilbur
43 Attention Deficit Hyperactivity Disorder Jennifer A. Reinhold
44 Alzheimer Disease Emily R. Hajjar
45 Parkinson Disease Karleen Melody & Anisha B. Grover
UNIT 10 Pharmacotherapy for Endocrine Disorders 46 Diabetes Mellitus
Lorraine Nowakowski-Grier & Veronica F. Wilbur
47 Thyroid Disorders Louis R. Petrone
UNIT 11 Pharmacotherapy for Immune Disorders 48 Allergies and Allergic Reactions
Lauren M. Czosnowski & Andrew M. Peterson
49 Human Immunodeficiency Virus Linda M. Spooner
UNIT 12 Pharmacotherapy for Hematologic Disorders 50 Pharmacotherapy for Venous Thromboembolism Prevention and Treatment, Stroke Prevention in Atrial Fibrillation, and Thromboembolism Prevention with Mechanical Heart Valves
Sarah A. Spinler
51 Anemias Kelly Barranger
UNIT 13 Pharmacotherapy in Health Promotion 52 Immunizations
Jean M. Scholtz
53 Smoking Cessation Tyan F. Thomas
54 Weight Loss Amy M. Egras
UNIT 14 Women’s Health 55 Contraception
Virginia P. Arcangelo
56 Menopause Elena M. Umland & Virginia P. Arcangelo
57 Osteoporosis Virginia P. Arcangelo
58 Vaginitis Virginia P. Arcangelo
UNIT 15 Integrative Approach to Patient Care 59 The Economics of Pharmacotherapeutics
Samir K. Mistry, Briana L. Santaniello, & Joshua J. Spooner
60 Integrative Approaches to Pharmacotherapy—A Look at Complex Cases Virginia P. Arcangelo, Andrew M. Peterson, Jennifer A. Reinhold, & Veronica F. Wilbur
UNIT 1 Principles of Therapeutics
1 Issues for the Practitioner in Drug Therapy
Virginia P. Arcangelo ■ Veronica F. Wilbur
Drug therapy is often the mainstay of treatment of acute and chronic diseases. An important role of health care practitioners is to develop a treatment plan with the patient; an integral part of the treatment plan of disease and health promotion is drug therapy. According to the Health in the United States (2014), from 2009 to 2012, of those persons aged 55 to 64, 55.6% used one to four prescription drugs and 20.3% used five or more during the last 30 days. Additionally, according to the National Ambulatory Medical Survey (2010), there were 2.6 billion drugs (75.1%) prescribed during office visits, 329.2 million drugs (72.5%) prescribed during visits to a hospital outpatient department, and 286.2 million drugs (80.3%) prescribed during visits to a hospital emergency department. The overall growth in spending on prescription drugs has slowed to 2.9% by 2011, but the overall spending equals $263 billion and accounts for a large share of national health care expenditures (CDC, FastStats, 2014). Therefore, it is imperative that prescribers have the best knowledge about principles of prescribing.
In developing a treatment plan that includes drug therapy, the prescribing practitioner considers many issues in achieving the goal of safe, appropriate, and effective therapy. Among them are drug safety and product safeguards, the practitioner’s role and responsibilities, the step-by-step process of prescribing therapy and writing the prescription, and follow-up measures. Particularly important are promoting adherence to the therapeutic regimen and keeping up-to-date with the latest developments in drug therapy.
Drug Safety and Market Safeguards In the United States, drug safety is ensured in many ways, but primarily by the U.S. Food and Drug Administration (FDA), which is the federal agency charged with conducting and monitoring clinical trials, approving new drugs for market and manufacture, and ensuring safe drugs for public consumption. Although the federal government provides guidelines for a pure and safe drug product, guidelines for prescribers of drug therapy are dictated both by state and federal governments and by licensing bodies in each state.
Clinical Trials Various legislated mechanisms are in place to ensure pure and safe drug products. One of these mechanisms is the clinical trial process by which new drug development is carefully monitored by the FDA. Every new drug must successfully pass through several stages of development (see Figure 1.1). The first stage is preclinical trials, which involve testing in animals and monitoring efficacy, toxic effects, and untoward reactions. Application to the FDA for investigational use of a drug is made only after this portion of research is completed.
FIGURE 1.1 Phases of drug development.
Clinical trials, which begin only after the FDA grants approval for investigation, consist of four phases and may last up to 9 years before a drug is approved for general use. During clinical trials, performed on informed volunteers, data are gathered about the proposed drug’s purity, bioavailability, potency, efficacy, safety, and toxicity.
Phase I of clinical trials is the initial evaluation of the drug. It involves supervised studies on 20 to 100 healthy people and focuses on absorption, distribution, metabolism (sometimes interchangeable with biotransformation), and elimination of the drug. In phase I, the most effective administration routes and dosage ranges are determined. During phase II, up to several hundred patients with the disease for which the drug is intended are subjects. The testing focus is the same as in phase I, except that drug effects are monitored on people with disease.
Phase III begins once the FDA determines that the drug causes no apparent serious adverse effects and that the dosage range is appropriate. Double-blind research methods (in which neither the study and control subjects nor the investigators know who is receiving the test drug and who is not) are used for data collection in this phase, and the proposed drug is compared with placebo. Usually several thousand subjects are involved in this phase, which lasts several years and during which most risks of the proposed drug are discovered. At the completion of phase III, the FDA evaluates data presented and accepts or rejects the application for the new drug. Approval of the application means that the drug can be marketed—but only by the company seeking the approval.
Once on the market, the drug enters phase IV or postmarketing surveillance.
Objectives at this stage are (1) to compare the drug with others on the market, (2) to monitor for long-term effectiveness and impact on quality of life, and (3) to analyze cost- effectiveness (Center Watch, 2015). During postmarketing surveillance, drugs can be taken off the market or restricted due to additional findings about the drug and side effects.
Prevention of Harm and Misuse The passage of the FDA’s Controlled Substances Act of 1970 established the schedule of ranking of drugs that have the potential for abuse or misuse. Drugs on the schedule are considered controlled substances. These drugs have the potential to induce dependency and addiction, either psychologically or physiologically. Box 1.1 defines the five categories of scheduled drugs, with Schedule 1 drugs having the greatest potential for abuse and Schedule 5 drugs the least.
BOX 1.1 Scheduled Drugs Schedule 1 drugs have a high potential for abuse. There is no routine therapeutic use
for these drugs, and they are not available for regular use. They may be obtained for “investigational use only” by applying to the U.S. Drug Enforcement Agency. Examples include heroin and LSD.
Schedule 2 drugs have a valid medical use but a high potential for abuse, both psychological and physiologic. In an emergency, a Schedule 2 drug may be prescribed by telephone if a written prescription cannot be provided at the time. However, a written prescription must be provided within 72 hours with the words authorization for emergency dispensing written on the prescription. These prescriptions cannot be refilled. A new prescription must be written each time. Examples include certain amphetamines and barbiturates.
Schedule 3 drugs have a potential for abuse, but the potential is lower than for drugs on Schedule 2. These drugs contain a combination of controlled and noncontrolled substances. Use of these drugs can cause a moderate to low physiologic dependence and a higher psychological dependence. A verbal order can be given to the pharmacy, and the prescription can be refilled up to five times within 6 months. Examples include certain narcotics (codeine) and nonbarbiturate sedatives.
Schedule 4 drugs have a low potential for abuse. They can cause psychological dependency but limited physiologic dependency. Examples include nonnarcotic analgesics and antianxiety agents, such as lorazepam (Ativan).
Schedule 5 drugs have the least potential for abuse. They contain a moderate amount of opioids and are used mainly as antitussives and antidiarrheals. Examples include antitussives and antidiarrheals with small amounts of narcotics.
Schedule drugs can be prescribed only by a practitioner who is registered and approved by the U.S. Drug Enforcement Agency (DEA), and in some states, practitioners must possess a controlled substance (CS) license as well. The DEA issues approved applicants a number, which must be written on the prescription for a controlled substance for the prescription to
be valid. The prescriber’s DEA number must also appear on a prescription that is being filled in another state.
Currently, in the United States, overdose emergencies and abuse of schedule drugs have become epidemic with over 259 million prescriptions written for painkillers (CDC Vital Statistics, 2014). To assist health care providers with safe prescribing practices, many states have enacted prescription drug monitoring programs (PDMPs). These programs are established and run by individual states through electronic databases that collect information on designated substances dispensed in the state. The DEA does not have involvement in any state PDMP program. According to the National Association of State Controlled Substance Authorities (NASCSA), in 2014, only one state did not have a PDMP. The program allows prescribers of controlled substance to look up patients for previous prescriptions of controlled substances including type of medication, amount, and name of the prescriber. The information obtained from this program helps to reveal those patients who prescriber shop and are receiving too many controlled substances. It also helps to start a conversation with the patients, exploring their health care needs.
National Provider Identifier The Administrative Simplification provisions of the Health Insurance Portability and Accountability Act of 1996 (HIPAA) mandated the adoption of standard unique identifiers for health care providers and health plans. This identification system improves the efficiency and effectiveness of electronically transmitting health information. The Centers for Medicare & Medicaid Services (CMS) has developed the National Plan and Provider Enumeration System (NPPES) to assign each provider a unique National Provider Identifier (NPI). Covered health care providers and all health plans and health care clearinghouses must use NPIs in the administrative and financial transactions adopted under HIPAA. The NPI is a 10-position, intelligence-free numeric identifier (10-digit number). The NPI does not carry other information about the health care provider, such as the health care provider’s specialty or in which state he or she practices. The NPI must be used in lieu of legacy provider identifiers in HIPAA standard transactions. Covered providers must also share their NPI with other providers, health plans, clearinghouses, and any entity that may need it for billing purposes.
The purpose of the NPI is to identify all health care providers by a unique number in standard transactions such as health care claims. NPIs may also be used to identify health care providers on prescriptions, in internal files to link proprietary provider identification numbers and other information, in coordination of benefits between health plans, in patient medical record systems, in program integrity files, and in other ways. HIPAA requires that covered entities (i.e., health plans, health care clearinghouses, and those health care providers who transmit health information in electronic form in connection with a transaction for which the Secretary of Health and Human Services has adopted a standard) use NPIs in standard transactions. The NPI is the only health care provider identifier that can be used in standard transactions by covered entities.
A health care provider may apply for an NPI through a web-based application process at https://nppes.cms.hhs.gov or by filling out and mailing a paper application to the NPI Enumerator. A copy of the application (CMS-10114), which includes the NPI Enumerator’s mailing address, is available upon request through the NPI Enumerator at 1- 800-465-3203, TTY 1-800-692-2326.
When applying for an NPI, providers are asked to include their Medicare identifiers as well as those issued by other health plans. A Medicaid identification number must include the associated state name. The legacy identifier information is critical for health plans to aid in the transition to the NPI. When the NPI application information has been submitted and the NPI assigned, NPPES sends the health care provider a notification that includes their NPI. This notification is proof of NPI enumeration and helps to verify a health care provider’s NPI.
Prescription versus Nonprescription Drugs Many drugs may now be obtained that were previously available only with a prescription, and at the prescription dosage. Although these drugs are commonly and legally obtained over the counter (OTC) without a prescription, approval for the drug must still be obtained from the FDA for specific uses in specific doses.
These drugs carry user warnings on the labels. Many have the potential for interacting adversely with prescribed drugs or complicating existing disease. The self-prescribed use of OTC drugs may delay diagnosis and treatment of potentially serious problems. On the other hand, the use of OTC drugs can be beneficial for treatment of self-limiting disorders that are not serious.
Generic Drugs versus Brand Name Drugs Substituting a generic drug for a brand name drug is a common practice. In many states, it is required. When the patent on a brand name drug expires, other drug manufacturers can then produce the same drug formula under its generic name (the generic name and formula of a drug are always the same; only the brand names change). This practice not only benefits the manufacturer but also decreases the cost to the consumer.
To ensure safety, the FDA must grant approval for these drugs, and rigorous testing is again required to ensure that all generic drugs meet specifications for quality, purity, strength, and potency. Generic drugs must demonstrate therapeutic equivalence to the brand name equivalent. They must be manufactured under the same strict standards and meet the same batch requirements for identity, strength, purity, and quality as the brand name drug. To obtain FDA approval, the generic drug is administered in a single dose to at least 18 healthy human subjects. Next, peak serum concentration and the area under the plasma concentration curve (AUC) are measured. The values obtained for the generic drug must be within 80% to 125% of those obtained for the brand name drug. Most generic drugs have a mean AUC within 3% of the brand name drug. There has been no reported therapeutic difference of a serious nature between brand name products and FDA-approved generic products. For more information, see Table 1.1, which presents FDA equivalency ratings for brand name and generic drugs.
TABLE 1.1 FDA Therapeutic Equivalence Ratings
U.S. Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs. (2010). Approved drug products with therapeutic equivalence evaluation (30th ed.).
Complementary and Alternative Medicine In the United States, the use of herbal preparations as treatments for disease and disease prevention has increased tremendously. According to the National Center for Complementary and Integrative Health, in 2012 approximately 33% of adults and 11% of children use some form of complementary approach to health care. The findings mirror similar surveys from 2007. The most popular products for adults (7.8%) and children (1.1%) are fish oils/Omega-3 fatty acids. These are followed by glucosamine and/or chondroitin (2.6%), probiotics/prebiotics (1.6%) and melatonin (1.3%) for adults, and for children melatonin (0.7%) (Clarke et al., 2015).
Historically, herbs were the first healing system used. Herbal medicines are derived from plants and thought by many to be harmless because they are products of nature. Some prescription drugs in current use, however, such as digitalis, are also “natural,” which is not synonymous with “harmless.” Before 1962, herbal preparations were considered to be drugs, but now they are sold as foods or supplements and therefore do not require FDA approval as drugs. Hence, there are no legislated standards on purity or quantity of active ingredients in herbal preparations. The value of herbal therapy is usually measured by anecdotal reports and not verified by research. Like synthetic products, herbal preparations may interact with other drugs and may produce undesirable side effects as well.
The Dietary Supplement Health and Education Act (1994) requires labeling about the effect of herbal products on the body and requires the statement that the herbal product has not been reviewed by the FDA and is not intended to be used as a drug. Complementary and alternative medicine (CAM) is discussed in Chapter 9.
Foreign Medications In today’s global society, practitioners will experience encounters with patients from many countries. These individuals may request refills of drugs for treating their chronic conditions. These drugs may have unrecognizable names, different dosages/dosage forms, or different active ingredients. Additionally, patients may get their drugs from online pharmacies in other countries because they are less expensive. Today, there is a proliferation of these online pharmacies, and only 3% comply with U.S. pharmacy laws (FDA, 2013). According to the World Health Organization, 80% of drugs are counterfeited in some countries (FDA, 2014). The Food and Drug Administration (FDA) has many resources for the practitioner to guide patients toward sound decision making about prescription drug acquisition.
Disposal of Medications Many medications can be potentially harmful if taken by someone other than the person for whom they are prescribed. Understand that improperly disposed drugs can leak into the environment, and the best disposal method is through community drug take-back programs. Almost all medicines can be safely disposed of if they are mixed with an undesirable substance, such as cat litter or coffee grounds, and placed in a closed container. Any personal information should be removed from the container by using a black marker or duct tape. Many communities have a drug take-back program for disposal, or drugs can be disposed of when the community collects hazardous material. Drugs should not be flushed down the toilet or drain unless the dispensing directions say this is permitted. Drugs permitted to be flushed can be found on the Web site http://www.fda.gov/Drugs/ResourcesForYou/Consumers/BuyingUsingMedicineSafely/EnsuringSafeUseofMedicine/SafeDisposalofMedicines/ucm186187.htm
Practitioner’s Role and Responsibilities in Prescribing Before prescribing therapy, the practitioner has a responsibility to gather data by taking a thorough history and performing a physical examination. Once the data are gathered and evaluated, one or more diagnoses are formulated and a treatment plan established. As noted, the most frequently used treatment modality is drug therapy, usually with a prescription or OTC drug.
If a drug is deemed necessary for therapy, it is essential for the practitioner to understand the responsibility involved in prescribing that drug or drugs and to consider seriously which class of medication is most appropriate for the patient. The decision is reached based on a thorough knowledge of diagnosis and treatment.
Drug Selection To determine which therapy is best for the patient, the practitioner conducts a risk–benefit analysis, evaluating the therapeutic value versus the risk associated with each drug to be prescribed. The practitioner then selects from a vast number of pharmacologic agents used for treating the specific medical problem. Factors to consider when selecting the drug or drugs are the subtle or significant differences in action, side effects, interactions, convenience, storage needs, route of administration, efficacy, and cost. Another factor in the decision may involve the patient pressuring the practitioner to prescribe a medication (because that is the expectation of many patients at the beginning of a health care encounter). Clearly, many responsibilities are inherent in prescribing a medication, and serious consequences may result if these responsibilities are not taken seriously and the prescription is prepared incorrectly.
Initial questions to ask when selecting drug therapy include “Is there a need for this drug in treating the presenting problem or disease?” and “Is this the best drug for the presenting problem or disease?” Additional questions are listed in Box 1.2.
BOX 1.2 Questions to Address When Prescribing a Medication
Is there a need for the drug in treating the presenting problem? Is this the best drug for the presenting problem? Are there any contraindications to this drug with this patient? Is the dosage correct? Or is it too high or too low? Does the patient have allergies or sensitivities to the drug? What drug treatment modalities does the patient currently use, and will the potential new drug interact with the patient’s other drugs or treatments? Is there a problem with storage of the drug? Does the dosage regimen (schedule) interfere with the patient’s lifestyle? For example, if a child is in school, a drug with a once- or twice-daily dosing schedule is more realistic than one with a four-times-daily schedule. Is the route of administration the most appropriate one? Is the proposed duration of treatment too short or too long? Can the patient take the prescribed drug? Has the patient been informed of possible side effects and what to do if they occur? Is there a genetic component to consider? What is the cost of the drug? What, if any, prescription plan does the patient have?
Concerns Related to Ethics and Practice Certain ethical and practical issues must be considered as well. One overriding issue may be the lack of a clinical indication for using a medication. As mentioned, many patients visit a practitioner with the sole purpose of obtaining a prescription. In seeking medical attention, the ill patient expects the health care provider to promote relief from symptoms. In today’s world, an abundance of information available in books, magazines, television, Web sites, and other media suggests that the health care provider can do this by prescribing a special medication. This expectation—that a magic pill or potion—the prescription—is the ticket that will relieve reflux, kill germs, end pain, and restore health—puts pressure on the practitioner to prescribe for the sake of prescribing. A common example of this involves the patient with a cold who seeks an antibiotic, such as penicillin. In such a situation, the practitioner has a responsibility to prescribe only medications that are necessary for the well-being of the patient and that will be effective in treating the problem. In the example of the patient with an uncomplicated head cold, an antibiotic would not be effective, and the responsible practitioner must be prepared to make an ethical and judicious decision not to prescribe an antibiotic and explain it to the patient.
Patient Education An integral part of the practitioner’s role and responsibility is educating the patient about drug therapy and the intended therapeutic effect, potential side effects, and strategies for dealing with possible adverse drug reactions. This may be explained verbally, with written instructions given, when appropriate. Instructions that are printed and handed to the patient must be readable, in a language that the patient can understand, and at the appropriate health literacy. If side effects are discussed in advance, the patient will know what to expect and will contact the prescriber with symptoms. There may be less likelihood that the patient will discontinue the drug before discussing it with the prescriber.
Medications can also have a placebo effect. Patients must believe that the drug will work for them to be committed to taking it as recommended. If that belief is not instilled in patients, the drug may not be perceived as effective and may not be taken as directed.
The practitioner may want to advise the patient to use only one pharmacy when filling prescriptions. The choice of only one pharmacy has several advantages, which include maintaining a record of all medications that the patient currently receives and serving as a double-check for drug–drug interactions.
Prescriptive Authority Prescribing practices of each practitioner are regulated by the state in which he or she practices. Each state determines practice parameters by statutes (laws enacted by the legislature), rules, and regulations (administrative policies determined by regulatory agencies). Each practitioner is responsible for knowing the laws and regulations in the state of practice.
Prescriptive authority is regulated by the State Board of Nursing, Board of Medicine, or Board of Pharmacy, depending on the state. States allow full practice authority, collaborative practice, supervised practice, or delegated practice. Full practice authority has no requirements for mandatory physician collaboration or supervision. Collaborative practice requires a formal agreement with a collaborating physician, ensuring a referral– consultant relationship. Supervised practice is overseen or directed by a supervisory physician. Delegated practice means that prescription writing is a delegated medical act. Regulations can be found at the Division of Professional Regulation for prescribers in each state.
Related to prescriptive authority issues is the issue of drug samples. Most drug companies engage in the promotional practice of distributing sample drugs to practitioners for use by patients. The Prescription Drug Marketing Act (PDMA), which was enacted in 1988 to protect the American consumer from ineffective drugs, also affects the receipt and dispensing of sample drugs. Prescription drugs can be distributed only to licensed practitioners (one licensed by the state to prescribe drugs) and health care entity pharmacies at the request of a licensed practitioner. PDMA protects the public in several ways. It forbids foreign countries to reimport prescription drugs; bans the sale, trade, and purchase of drug samples; prohibits resale of prescription drugs purchased by hospitals, health care entities, and charitable organizations; requests practitioners to ask for drug samples in writing; and regulates wholesale distributors of prescription drugs by requiring licensing in states where facilities are located. There are penalties for violation of the act. This act affects the distribution and use of pharmaceutical samples.
Because these samples are freely available, it might be assumed that they can be distributed by all practitioners, but this is not the case. The practitioner must be aware of the rules that govern requesting, receiving, and distributing these agents because the rules vary from state to state.
Specific procedures are required with drug samples. The pharmaceutical representative’s Sample Request Form must be signed. It includes the name, strength, and quantity of the sample. The sample must be then recorded on the Record of Receipt of Drug Sample sheet. The samples must be stored away from other drug inventory and where unauthorized access is not allowed or in a locked cabinet or closet in a public area. Samples are to be inspected monthly for expiration dates, proper labeling and storage, presence of intact packaging and labeling, and appropriateness for the practice. If a sample has expired,
it must be disposed of in a manner that prevents accessibility to the general public. It cannot be disposed into the trash.
When distributing samples, each must be labeled with the patient’s name, clear directions for use, and cautions. All samples are to be dispensed free of charge along with pertinent information. The medication is then documented in the patient’s chart with dose, quantity, and directions.
Adverse Drug Events Prescription and nonprescription drugs are an increasing part of life in the United States. Between the years of 2009 and 2012, there were 48.7% of individuals who took at least one prescription drug in the last 30 days (CDC, FastStats, 2015). Adverse drug events (ADE) have consequently become an increasing problem resulting in adverse events both in the inpatient and outpatient settings. Due to the magnitude of the problem, the Home of the Office of Disease and Health Promotion have created a National Action Plan for Adverse Drug Event Prevention 2014 (http://health.gov/hcq/ade.asp). Therefore, the prudent prescriber must always be aware of any medications presenting for health care. Chapter 3 reviews the impact of ADE in depth.
Lack of Drug Knowledge There can be a lack of knowledge about indications and contraindications for drugs. This includes underuse, overuse, and misuse of drugs. An example of underuse is failure to prescribe an inhaled corticosteroid for an asthmatic patient who uses his albuterol daily. An example of overuse is prescribing an antibiotic for a cold or prescribing an antihypertensive drug for someone whose blood pressure is elevated because he is taking pseudoephedrine (Sudafed). An example of misuse is prescribing penicillin to someone for a strep throat who has identified a clear allergy to the drug.
Dosing errors occur when a larger dose is prescribed than needed or the conversion from oral to intravenous is too high. This is especially problematic with pediatrics for antibiotics (Aseeri, 2013). For example, prescribing a dose of Augmentin that is greater than the suggested amount or starting a patient on 30 mg paroxetine instead of 20 mg may increase anxiety.
Lack of knowledge about drug–drug interactions can also cause errors. For example, many drugs interfere with warfarin and cause increased bleeding if taken together. The prescriber must be aware of the potential for drug–drug interactions (see Chapter 3 for more information).
Lack of Patient Information A common error in prescribing is failure to obtain an adequate history from the patient. Often an adequate drug history is not obtained and the provider does not specifically inquire about herbal preparations or OTC medications. Also, information on allergies to medications is not always obtained. In addition to allergies, it is imperative to ascertain the reaction to the medication. Nausea is not considered an allergic reaction. An allergy history should be taken and documented at each visit before a new medication is prescribed. Additionally, asking multiple times about allergies or reactions to drugs during a visit is a safety cross-check to responsible prescribing.
Poor Communication Poor communication between health care providers, pharmacists, and patients can be a result of poor handwriting, incorrect abbreviations, misplaced decimals, and misunderstanding of verbal prescriptions. These potential errors can be mitigated through the use of electronic health record (EHR); however, new errors can occur if the practitioner does not click on the correct medication. Additionally, there are areas in the United States where providers still handwrite prescriptions. Poor communication also results when the prescriber fails to discuss potential side effects or ask about side effects at subsequent visits.
Special Population Considerations Doses for children are usually based on weight in kilograms. The prescriber has a responsibility to calculate the dose and write the correct dose, rather than relying on the pharmacist to calculate the dose. See Chapter 4 for more information about pediatric drug dosing.
Elderly patients may have some difficulty hearing or reading small print. Additionally, they may be taking multiple prescription medications and OTC medications. The prescriber needs to be specific about when the patient should take each medication and if one drug cannot be taken with others. When the practitioner prescribes for the elderly, he or she must consider renal function because some medications can cause toxicity, even in small doses, with decreased renal function. Chapter 6 reviews the considerations necessary for good prescribing in the elderly.
Pharmacogenomics Recently, pharmacogenomics has gained importance in prescribing medication. The way a person responds to a drug is influenced by many different genes. Without knowing all of the genes involved in drug response, it has not been possible to develop genetic tests that could predict a person’s response to a particular drug. Knowing that people’s genes show small variations in the DNA base makes genetic testing for predicting drug response possible. Genetic factors can account for 20% to 95% variability of the patient’s reaction to a drug. Pharmacogenomics examines the inherited variations in genes that dictate drug response and explores the ways these variations can be used to predict the response a patient will have to a drug. Pharmacogenetic testing may enable providers to understand why patients react differently to various drugs and to make better decisions about therapy. This understanding may allow for highly individualized therapeutic regimens. This concept is discussed in detail in Chapter 10.
Steps of the Prescribing Process At each visit, a medication history is obtained with the name of the drug, dosage, and frequency of administration. Information on any allergies should also be obtained. It is also helpful if the patient brings his or her actual drugs to the visit.
Multiple steps (Figure 1.2) are involved in prescribing drugs and evaluating their effectiveness. Again, the first step is determining an accurate diagnosis based on the patient’s history, physical examination, and pertinent test findings.
FIGURE 1.2 Process for prescribing.
Next, in selecting the best agent, the practitioner thoroughly evaluates the patient’s condition, taking into consideration the effect that various medications may have on the patient and the disorder, the expected outcomes of therapy, and other variables (Box 1.3). When prescribing any drug therapy, the practitioner must have a solid knowledge and background in the pathophysiology of disease, pharmacotherapeutics, pharmacokinetics, pharmacodynamics, and any interactions (see Chapters 2 and 3).
BOX 1.3 Variables to Consider in Prescribing a Medication Age Sex Race
Weight Culture Allergies Pharmacogenomics Other diseases or conditions Other therapies
Prescription medications Over-the-counter medicines Alternative therapies
Previous therapies Effectiveness Adverse effects Adherence
Socioeconomic issues Insurance status Income level Daily schedule Living environment Support systems
The practitioner needs to be knowledgeable about the best class of drugs for the diagnosed disorder or presenting problem, the recommended dosage, potential side effects, possible interactions with other drugs, and special prescribing considerations, such as required laboratory tests, contraindications, and patient instructions. To select the correct medication, the practitioner must thoroughly understand the pathophysiology of the condition being treated and the natural history of the disease. This information allows the practitioner to decide at which point in the disease process intervention with drug therapy is indicated because in many diseases or disorders, nonpharmacologic therapies are tried before drug therapy is initiated.
Next, the practitioner sets goals for therapy. Goals need to be realistic and outcomes measurable. All interventions, nonpharmacologic and pharmacologic, are initiated to meet these goals, and evaluation of the therapy’s efficacy is based on these goals.
Selecting Most Appropriate Agent For most disease entities, there is a recommended first-line therapy—that is, research shows certain agents to be more effective than others. Once initiated, the first-line therapy is evaluated and either continued or changed. If the desired goals are not achieved, or if an adverse reaction occurs, second-line therapy is initiated. The second-line therapy is then evaluated. If this therapy is not tolerated or efficacious, a third-line therapy is initiated, and so on. The practitioner continually evaluates the patient’s response to therapy and maintains current therapy or changes it as indicated by the patient’s response. For more information, see the case study outlining the prescribing process. Case studies such as this one are used throughout the text.
Consideration of Special Populations Another step in prescribing drugs is considering specific concerns related to special populations, such as children, pregnant or breast-feeding women, and the elderly. Cultural beliefs are also considered to ensure that the drug regimen honors individual and family customs and preferences. Pharmacogenomics are gaining in popularity when considering which drug to prescribe.
Identifying Outcomes Expected outcomes can include improvement in clinical symptoms or pathologic signs or changes in biochemistry as determined by laboratory tests. To assess whether expected outcomes have been achieved, the practitioner reviews data collected on subsequent visits, evaluates the effectiveness of drug therapy, and investigates any adverse reactions.
The frequency of follow-up visits is determined by the disease and the patient’s response to treatment. While outcomes are being assessed, the practitioner educates the patient about the outcomes of therapy as well. Topics for discussion include drug benefits, side effects, dosage adjustments, and monitoring parameters.
The patient as well as the practitioner must be informed about any undesirable outcomes of therapy with a prescription drug. Reactions that may be expected and must be discussed include side effects, drug or food interactions, and toxicity. Unexpected reactions include allergic reactions or intolerance to a drug. If a patient experiences a serious adverse drug reaction, the practitioner files a report with the FDA’s MedWatch program on a special form obtainable from MedWatch (5600 Fishers Lane, Rockville, MD 20852-9787 or it can be reported online at https://www.accessdata.fda.gov/scripts/medwatch/; see Chapter 3 for a sample of the MedWatch form). Similarly, adverse reactions to vaccines are reported through the Vaccine Adverse Event Reporting System (VAERS) online at http://vaers.hhs.gov/esub/index#Online or by mail by completing a VAERS form requested by calling 1-800-822-7967 and mailing it to VAERS, P.O. Box 1100, Rockville, MD 20849-1100. Adverse events are discussed in Chapter 4.
Writing the Prescription The practice of handwriting prescriptions is slowly becoming an exercise of the past; however, there are still instances where a practitioner needs to know the steps. The prescription is a form of communication between the practitioner and the pharmacist. It is also the basis for written directions to patients, and it is a legal document. Each prescription should be clearly written to avoid errors of misinterpretation in filling the prescription. Although potentially serious errors occur infrequently, they are avoidable and should not occur at all.
An early step in the prescribing process involves ensuring that common but potentially serious errors are not made. The first is failure to identify a patient’s allergies, particularly to a medication. In identifying a drug allergy, the practitioner should also investigate the kind of reaction experienced with the medication to differentiate between a true, life-threatening drug allergy and less serious drug sensitivity. Some cross-sensitivities must also be considered. Another error is failure to instruct the patient to stop a previously prescribed medication that treats the same condition. In some instances, an additional medication may be prescribed to increase the effect for the same problem, but the patient must be made aware of this. Otherwise, the original medication must be canceled. Failure to recognize the effect of a prescribed drug on other diseases or drugs can lead to potentially serious effects. There are now programs that can do multiple checks for interactions. One of these is Epocrates for mobile devices and desktops.
Date, Name, Address, and Date of Birth There are standard components of any prescription. One is the date and another is the full name, address, and date of birth of the patient. The name should be the patient’s given name (the one on the medical record) and not a nickname. If a different name is used each time, the patient could have multiple records in pharmacy record-keeping systems. The address should be the current home address of the patient and not a work address or a post office box.
Prescriber’s Name, Address, and Phone Number The next components are the name, address, and phone number of the prescriber and the collaborating physician if required by state law or regulations. This enables the pharmacist to contact the prescriber if there is a question about the prescription.
Name of Drug Of course, the name of the drug is the most essential part of the prescription. Ideally, the generic name (with the trade or brand name in parentheses) is used. The name must be legible to avoid errors in filling the prescription correctly. For instance, some drugs have names that are commonly confused or misread, such as Norvasc and Navane, Prilosec and Prozac, carboplatin and cisplatin, and Levoxine and Lanoxin. Severe problems may result if the wrong drug is supplied erroneously. Adding the diagnosis to the prescription, although optional, can help the pharmacist avoid misinterpreting the prescribed drug.
Dose, Dosage Regimen, and Route of Administration The drug dose is essential because many drugs are available in various strengths. The dose is written in numerals. If the dose is a fraction of 1, it is written in decimal form with a leading zero to the left of the decimal point (e.g., 0.75). However, a whole number should not be followed by a decimal point and a trailing zero (10.0 could be misinterpreted as 100). The numeric dose is followed by the correct metric specification such as milligram (mg), gram (g), milliliter (mL), or microgram (mcg). Many practitioners spell out microgram to avoid confusion with milligram. Some drugs are manufactured in units that should be specified, and the term unit should be written out (insulin 10 units, not 10 U). Usually, the strength of drugs that are combination products or that are manufactured only in one strength do not need to be included. The route of the drug is specified as well. (Routes of administration are discussed in Chapter 2.)
The prescription also specifies how frequently the drug is to be taken. A drug prescribed to be taken as needed is termed a prn drug. For example, dosage frequency can be written as “prn every 4 hours” (or another appropriate interval) for the problem for which the drug is prescribed (e.g., “as needed for nausea”). It is good practice to write out the number (10–ten), especially with controlled substances. Any special instructions, such as “after meals,” “at bedtime,” or “with food,” also should be specified. If the dose is once a day it is safer practice to write out daily than to write OD because this can be confused with every other day.
The prescription also includes the number of pills, vials, suppositories, or containers or amount in milliliters or ounces to be dispensed. Prescription reimbursement or health care insurance programs often allow for 30- or 90-day supplies to be dispensed at a time, working with the pharmacist is imperative for optimal prescribing practices. They are the best connection regarding the rules of various prescription plans. The prescription indicates whether the prescription may be refilled and the number of refills permitted.
When prescribing a new drug for a patient, the practitioner may want to consider prescribing just a few doses or a 7-day supply initially. Alternatively, samples may be provided, if allowed by law or regulations. This allows the prescriber to determine if the patient can tolerate the drug and if it is effective. When deciding on the number of refills, the practitioner may decide when the patient should return for a follow-up visit and allow just the number of refills that will take the patient until the next visit to ensure that the patient returns. Some drug prescriptions cannot be refilled. For all Schedule 2 drugs, for example, a new prescription must be written each time.
Allowable Substitutions There are many generic equivalents for brand name drugs. Indication of whether a substitution is allowed is a part of the prescription. As discussed earlier, a generic drug substitute must have the same chemical composition and dosage as the brand name drug originally prescribed. In many states, a generic drug will automatically be substituted for a brand name drug. If there is a medical reason to require a brand name drug (that has a generic equivalent), “Brand Medically Necessary” must be written on the prescription.
Prescriber’s Signature and License Number The signature of the prescriber is required. It should be legible and should be the person’s legal signature. The license number of the prescriber or the collaborating physician is required on the prescription in some, but not all, states depending on the rules and regulations that govern the prescriber. In some instances, the DEA number of the prescriber is also required, especially when prescribing between states or prescribing a controlled substance. Figure 1.3 illustrates a blank prescription and a completed prescription. Each state has specific requirements for components on a printed prescription. The practitioner must be in compliance with state regulations and may prescribe only in the state in which he or she holds a license. Although the prescription may be filled in another state (if allowed by state regulations), a DEA number is usually required. An NPI number must be on each prescription along with a serial number of the prescription form. If the practitioner is a federal employee, he or she may prescribe in any federal facility.
FIGURE 1.3 Example of a blank prescription form (left) and a completed form (right).
Any drug prescribed should be clearly documented in the medical record with date of order, dosage, amount prescribed, and number of refills. It is helpful to have a specific area in the record to record all drugs taken by the patient—prescription, OTC, and CAM—for ease of audit, reference, and communication among health care professionals.
Electronic Prescriptions Electronic prescribing has become increasingly popular. Health care technology reduces medication errors with the use of drug-checking software, which checks the medication dose, potential interactions with other medications the patient may be taking, and the patient’s known allergies. This drug-checking software may be part of the EHR or of a freestanding e-prescribing system. Integrated EHRs can calculate dosing based on a patient’s weight and carry out other contextual medication checking against a patient’s laboratory results, age, and disease states. In addition, computer systems provide pick lists of each clinician’s favorite medications with a precalculated dose, frequency, and route, reducing the opportunity for clinicians to order inappropriate amounts of medications with the wrong frequency and route.
E-Prescribing improves the legibility of prescriptions and the rate of completed prescriptions. Patients no longer need to carry paper copies of a prescription to a pharmacy and are more likely to have formulary-compliant medications prescribed for them and to find their prescriptions waiting for them when they arrive at the pharmacy. This leads to greater patient convenience, shorter wait times, and increased compliance with formulary requirements. Electronic prescribing has been said to show a 12% to 20% decrease in ADEs (Figge, 2009).
With electronically generated prescriptions, there are no handwriting misinterpretations and no manual data entry. Correct dosages are built into the software. They assist with formulary requirements based on the patient’s insurance and maintain allergy profiles and ADEs. They also serve to decrease drug–drug interactions.
Adherence Issues A prescribed drug must be used correctly to produce optimal benefits. Patient nonadherence to a prescribed regimen leads to less-than-optimal outcomes, such as progression of the disease state and an increased incidence of hospitalizations. Studies demonstrate that the more complex the treatment regimen, the less likely the patient is to follow it. Benner (2009) studied 5,759 patients taking antihypertensive and lipid-lowering drugs. In patients with 0, 1, and 2 prior medications, 41%, 35%, and 30% of patients were adherent, respectively, to antihypertensive and lipid-lowering therapy. Of patients with 10 or more prior medications, 20% were adherent.
Karter (2009) studied 27,329 subjects prescribed new medications. Pharmacy utilization data were used. It was found that 22% of patients had the prescription filled zero or one times. The proportion of newly prescribed patients who never became ongoing users was eight times greater than the proportion who maintained ongoing use, but with inadequate adherence. Four percent of those who had the prescription filled at least two times discontinued therapy during the 24-month follow-up. Nonadherence was significantly associated with high out-of-pocket costs and clinical response to therapy.
Several variables are associated with improved adherence to a drug regimen. These include variables associated with the patient’s perception of the encounter and of the benefit of the treatment. If a patient is nonadherent to the prescribed regimen, it is important to document that in the chart. The risks of nonadherence are discussed, and that discussion is documented. It is essential to ask why the patient is not following the prescribed treatment, and actions to rectify the problem should be taken. All of this is documented. One issue may be that the patient is unable to swallow the pill. The medicine may be available in liquid form, or the pill may be split or crushed. The practitioner needs to review and understand the factors that affect adherence to a regimen (Box 1.4).
BOX 1.4 Factors Influencing the Patient’s Adherence to a Medication Regimen
Approachability of the health care provider Perception of respect with which he or she is treated by the practitioner Belief that the therapy is beneficial Belief that the benefits of therapy outweigh the risks or side effects Degree to which the patient participates in developing the treatment regimen Cost of the regimen Simplicity of the regimen Understanding of the treatment regimen Degree to which the patient feels that expectations are being met
Degree to which the patient perceives his or her concerns are important and being addressed Degree to which the practitioner motivates the patient to adhere to the regimen Degree to which the regimen is compatible with the patient’s lifestyle
Updating Drug Information Many sources of drug information can be accessed by practitioners who must keep current on changes in drug therapy and continually update their fund of knowledge. Resources include reference books, pharmacists (who are expertly informed about drugs, interactions, dosages, etc.), easy-to-carry drug handbooks and pocket guides for quick reference, and online databases and programs for mobile devices and desktop computers (Tables 1.2 and 1.3).
TABLE 1.2 Common Drug Reference Books
TABLE 1.3 Online Drug Reference Data
Case Study* A.J. is a 16-year-old who has just started soccer practice at school. She complains of increased shortness of breath with exercise, and describes having a hard time catching her breath when she runs, which she does five to six times a week. She does not wake up at night with a cough or shortness of breath, and has no problems at any other time except in the spring when the trees start to blossom. The soccer coach advised A.J.’s mother to seek health care because A.J. had a very difficult time breathing at practice that afternoon. A.J. also has a history of eczema and seasonal allergies for which she takes an over-the counter antihistamine when symptoms get severe.
Social History: Nonsmoker. Lives in an urban area with mother, father, and brother. Does not use street drugs.
Family History: Father has a history of asthma. Physical examination:
Nose: Mucosa pale and boggy bilaterally Lungs: Respirations 26 and shallow; diffuse expiratory wheezing; peak flow 340
Diagnosis: Mild persistent asthma
Questions 1. List specific goals of therapy for A.J.