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Medical Dictionary


noun \ˈdrəg\

Medical Definition of DRUG

a :  a substance used as a medication or in the preparation of medication b according to the Food, Drug, and Cosmetic Act (1) :  a substance recognized in an official pharmacopoeia or formulary (2) :  a substance intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease (3) :  a substance other than food intended to affect the structure or function of the body (4) :  a substance intended for use as a component of a medicine but not a device or a component, part, or accessory of a device
:  something and often an illicit substance that causes addiction, habituation, or a marked change in consciousness
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