Chapter 1: Issues for Practitioners in Drug Therapy

Drug approval in the United States is governed by the FDA, which mandates rigorous processes starting with preclinical animal testing, followed by four phases of human clinical trials, including assessment of absorption, distribution, metabolism, and elimination (ADME), efficacy in diseased populations, and long-term postmarketing surveillance (Phase IV). Special provisions like Fast Track and Emergency Use Authorization (EUA) exist to expedite review for critical medications. Practitioners must adhere to federal and state laws, including the Controlled Substances Act of 1970, which classifies drugs based on abuse potential, requiring prescribers to register with the DEA and utilize Prescription Drug Monitoring Programs (PDMPs) to mitigate misuse. Before prescribing, the clinician must perform a thorough risk-benefit analysis, ensuring the selected drug is appropriate for the diagnosis and factoring in patient-specific variables such as age, weight, culture, pharmacogenomics, existing conditions, and interactions with other treatments, including over-the-counter and herbal preparations, which lack stringent FDA purity standards. Modern prescribing practices increasingly utilize electronic health records (EHRs) and e-prescribing, which reduce common errors (like illegibility or incorrect dosing) through automated drug-checking software. Essential elements of a legal prescription include patient and provider identification (such as the National Provider Identifier or NPI), the drug's generic name, accurate dose, clear regimen, and specific directions regarding generic substitution. Crucially, patient safety involves educating individuals about the intended effect, potential adverse drug events (ADEs), serious black box warnings, and ensuring adherence—a process highly influenced by the simplicity of the regimen, cost, and the patient's perception of the care provider and treatment benefit.