Final answer:
The item that is not a drug reference among the options provided is C) medical dictionary. Drug references are specialized resources that provide detailed drug information, which a medical dictionary does not primarily do.
Step-by-step explanation:
The answer to the question: Which of the following is not a drug reference? is C) medical dictionary. A drug reference typically provides specific information on medications, such as dosing, administration, side effects, and so on. While a medical dictionary may contain some drug-related information, its primary purpose is to provide definitions of medical terms and is therefore not primarily a drug reference.
The PDR (Physicians' Desk Reference) is a compilation of drug prescribing information and is considered a drug reference. The USP/NF (United States Pharmacopeia/National Formulary) is a set of standards for the quality, purity, strength, and consistency of drugs, food ingredients, and dietary supplement products in the United States, also a drug reference. The AHFS (American Hospital Formulary Service) provides an extensive listing of drug information, primarily for healthcare professionals, and is a recognized drug reference as well.