Davis’s Drug Guide for Nurses Eighteenth Edition

Book Preface

HOW TO USE DAVIS’S DRUG GUIDE FOR NURSES

Davis’s Drug Guide for Nurses provides comprehensive, up-to-date drug information in well-organized, nursing-focused monographs. It also includes extensive supplemental material in 14 appendices, thoroughly addresses the issue of safe medication administration, and educates the reader about 50 different therapeutic classes of drugs. In this 18th edition, we have continued the tradition of focusing on safe medication administration by including Medication Safety Tools and even more information about health care’s most vulnerable patients: children, the elderly, pregnant women, and breast feeding mothers. Look for more Pedi, Geri, OB, Lactation, and Rep headings in the monographs. We have also included a BEERS label at the top of applicable drug monographs for those medications listed in the Beers Criteria developed by the American Geriatrics Society. These medications are considered to be potentially inappropriate for use in older adults because they are associated with more risk than benefit in this patient population. In addition, we’ve included information relevant to Canadian students and nurses. You’ll find an appendix comparing Canadian and U.S. pharmaceutical practices, more Canada-only combination drugs in the Combination Drugs appendix, and additional Canadian brand names in the drug monographs. To help you find this information quickly, we’ve also added a maple leaf icon ( ) in the index next to each Canadian entry. We have added pharmacogenomic information throughout numerous monographs to guide the nurse in selecting and monitoring various drug therapies. To help you find this information quickly, we’ve added a double helix icon ( ) to denote this information as it applies to specific drugs. Use this book to enhance your competence in implementing and evaluating medication therapies. The following sections describe the organization of Davis’s Drug Guide for Nurses and explain how to quickly find the information you need.

Safe Medication Use Articles “Medication Errors: Improving Practices and Patient Safety,” “Detecting and Managing Adverse Drug Reactions,” “Overview of Risk Evaluation and Mitigation Systems (REMS),” “Special Dosing Considerations,” and “Educating Patients About Safe Medication Use” comprise the safe medication use articles and provide an overview of the medication safety issues that confront practitioners and patients. Leading off this series, the medication errors article familiarizes you with the systems issues and clinical situations repeatedly implicated in medication errors and suggests practical means to avoid them. It also teaches you about high alert medications, which have a greater potential to cause patient harm than other medications. “Detecting and Managing Adverse Drug Reactions” explains the different types of adverse reactions and provides guidance on how to detect and manage them. “Risk Evaluation and Mitigation Strategies (REMS)” explains strategies developed by the pharmaceutical industry and required by the Food and Drug Administration (FDA) to minimize adverse drug reactions from potentially dangerous drugs. We have highlighted the drugs that currently have approved REMS programs associated with their use by adding a REMS label at the top of applicable drug monographs. “Special Dosing Considerations” identifies the patient populations, such as neonates and patients with renal impairment, who require careful dose adjustments to ensure optimal therapeutic outcomes.
“Educating Patients About Medication Use” reviews the most important teaching points for nurses to discuss with their patients and their families. In addition to these safety articles, other critical information is highlighted in red throughout the drug monographs. This allows the reader to quickly identify important information and to see how nursing practice, including assessment, implementation, and patient teaching, relates to it.

Classifications Profile

Medications in the same therapeutic class often share similar mechanisms of action, assessment guidelines, precautions, and interactions. The Classifications Profile provides summaries of the major therapeutic classifications used in Davis’s Drug Guide for Nurses. It also provides patient teaching information common to all agents within the class and a list of drugs within each class.

Medication Safety Tools

Updated for this edition is a section with tables and charts that nurses can use for a quick but thorough reference to information that will help them avoid making medication errors. It includes lists of drugs that are associated with adverse reactions and falls in the elderly; proper dosing for pediatric intravenous medications; confused drug names; FDA-approved Tall Man letters and more.

Drug Monographs

Drug monographs are organized in the following manner:
High Alert Status: Some medications, such as chemotherapeutic agents, anticoagulants, and insulins, have a greater potential for harm than others. These medications have been identified by the Institute for Safe Medication Practices as high alert drugs. Davis’s Drug Guide for Nurses includes a high alert tab in the upper right corner of the monograph header in appropriate medications to alert the nurse to the medication’s risk. The term “high alert” is used in other parts of the monograph as well, to help the nurse administer these medications safely. See the article “Medication Errors: Improving Practices and Patient Safety” for a complete list of high alert medications in Davis’s Drug Guide for Nurses. Refer to www.ISMP.org for all solutions, groups, and individual high alert drugs.

Generic/Brand Name: The generic name appears first, with a pronunciation key, followed by an alphabetical list of trade names. Canadian trade names are preceded by a maple leaf ( ). Many brand names have been discontinued by the manufacturer requiring nurses to know the generic names of drugs. Brand names that have been discontinued have a slash through them (Decadron). Common names, abbreviations, and selected foreign names are also included.

Classification: The therapeutic classification, which categorizes drugs by the disease state they are used to treat, appears first, followed by the pharmacologic classification, which is based on the drug’s mechanism of action.

Controlled Substance Schedule: All drugs regulated by federal law are placed into one of five schedules, based on the drug’s medicinal value, harmfulness, and potential for abuse or addiction. Schedule I drugs, the most dangerous and having no medicinal value, are not included in Davis’s Drug Guide for Nurses. (See Appendix H for a description of the Schedule of Controlled Substances.)
Pregnancy Category: The FDA recently recommended discontinuation of the Pregnancy Category system (A, B, C, D, and X) since this categorization may not appropriately communicate the risk that a drug may have during pregnancy or breast feeding. Based on this guidance, the Pregnancy Categories have been removed from each of the drug monographs. These pregnancy letter categories have been replaced in drug prescribing information and Patient/Family Teaching with a narrative summary that describes the potential risk of using the drug during pregnancy and breast feeding, as well as the potential impairment of fertility in women and men of reproductive potential. The drug monographs have been enhanced with this detailed information in these patient populations and highlighted by a Rep tag to call the user’s attention to reproductive information.

Indications: Medications are approved by the FDA for specific disease states. This section identifies the diseases or conditions for which the drug is commonly used and includes significant unlabeled uses as well.

Action: This section contains a concise description of how the drug produces the desired therapeutic effect.

Pharmacokinetics: Pharmacokinetics refers to the way the body processes a medication by absorption, distribution, metabolism, and excretion. This section also includes information on the drug’s half-life.

Absorption: Absorption describes the process that follows drug administration and its subsequent delivery to systemic circulation. If only a small fraction is absorbed following oral administration (diminished bioavailability), then the oral dose must be much greater than the parenteral dose. Absorption into systemic circulation also follows other routes of administration such as topical, transdermal, intramuscular, subcutaneous, rectal, and ophthalmic routes. Drugs administered intravenously are 100% bioavailable.

Distribution: This section comments on the drug’s distribution in body tissues and fluids. Distribution becomes important in choosing one drug over another, as in selecting an antibiotic that will penetrate the central nervous system to treat meningitis or in avoiding drugs that cross the placenta or concentrate in breast milk. Information on protein binding is included for drugs that are 95% bound to plasma proteins, which has implications for drug-drug interactions.

Metabolism and Excretion: Drugs are primarily eliminated from the body either by hepatic conversion to active or inactive compounds (metabolism or biotransformation) and subsequent excretion by the kidneys, or by renal elimination of unchanged drug. Therefore, drug metabolism and excretion information is important in determining dosage regimens and intervals for patients with impaired renal or hepatic function. The creatinine clearance (CCr) helps quantify renal function and guides dosage adjustments. Formulas to estimate CCr are included in Appendix E.

Half-Life: The half-life of a drug is the amount of time it takes for the drug concentration to decrease by 50% and roughly correlates with the drug’s duration of action. Half-lives are given for drugs assuming the patient has normal renal or hepatic function. Conditions that alter the half-life are noted.