A patient asks a nurse why a friend who is taking the same drug responds differently to that drug. The nurse knows that the most common variation in drug response is due to differences in each patient's:

Question

a. drug receptor sites.
b. hypersensitivity potential.
c. metabolism of drugs.
d. psychosocial response.

Answer 1

ANS: C
The most common source of genetic variation in drug response is related to alterations in drug metabolism and is determined by genetic codes for various drug-metabolizing isozymes. There are known genetic differences in codes for drug target sites, but these are not as numerous as those for metabolic isozymes. Hypersensitivity potential is also genetically determined, but variations produce differences in adverse reactions to drugs and not in drug effectiveness. Psychosocial responses vary for many, less measurable reasons, such as individual personalities and variations in cultures.