Which aspect of genetic makeup is most likely to alter a person's response to medication?.

Choice A rationale:
Trough levels are the lowest concentration in the patient’s bloodstream, hence they are not the best indicator of the amount of circulating medication.
Choice B rationale:
The term ‘Drug’ is too general and does not specifically refer to the amount of medication in the patient’s bloodstream.
Choice C rationale:
Peak levels are the highest concentration of a drug in the patient’s bloodstream after administration. This is when the amount of the medication in the body is likely to be highest.
Choice D rationale:
Therapeutic levels refer to the range in which a drug is expected to be effective without causing any serious problems to the patient. It does not directly indicate the amount of circulating medication.

Choice A rationale:
An increase in the amount of lipid-soluble drugs in the system can occur with decreased albumin and globulin levels, but it does not cause the most concern.
Choice B rationale:
Increased free protein-bound drugs available can lead to an increased potential for adverse drug reactions. This is because these drugs are usually more active and can lead to toxicity.
Choice C rationale:
Water-soluble drugs being absorbed more completely is not typically a concern with decreased albumin and globulin levels.
Choice D rationale:
While metabolism of protein-bound drugs may be decreased, leading to an increased potential for adverse reactions, this is not the primary concern with decreased albumin and globulin levels.