Which term is the conversion of a drug into its active form?

• A. Absorption
• B. Active Transport
• C. Biotransformation
• D. Elimination

Answer: (C)

Drug activation occurs through biotransformation, the body's metabolic process that converts a drug into a more active (or differently active) form. The liver is the primary site, using enzymes such as the cytochrome P450 system to add or modify functional groups, producing active metabolites from prodrugs or sometimes additional active forms from parent compounds. This transformation helps the drug exert its therapeutic effect and can also prepare it for elimination.

Absorption is about how the drug enters the bloodstream, active transport refers to cellularly moving substances against a gradient, and elimination is the process of removing the drug from the body. Biotransformation specifically describes the chemical changes the body makes to the drug, including activation. For example, a prodrug like codeine is converted to its active form, morphine, through metabolism.