Which factor among those listed can influence drug metabolism due to body composition?

• A. Fat to muscle ratio
• B. Eye color
• C. Shoe size
• D. Favorite cuisine

Answer: (A)

Body composition, especially the fat-to-muscle ratio, influences how a drug is distributed in the body. Lipophilic drugs tend to partition into fatty tissue, so having more fat relative to muscle increases the volume of distribution. This means more of the drug sits in fat stores and is released more slowly, which can alter the effective exposure of the tissues to the drug and can slow down its apparent metabolism and clearance. In contrast, choices like eye color, shoe size, or favorite cuisine don’t reflect body fat or lean mass and thus don’t impact how drugs are distributed or processed.