A nurse is preparing to administer amoxicillin 500 mg PO. Available is amoxicillin 250 mg tablets.

How many tablets should the nurse administer?
(Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

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:
While distribution can affect a person’s response to medication, it is not the aspect of genetic makeup most likely to alter this response.
Choice B rationale:
Absorption can affect how a drug is taken up by the body, but it is not the aspect of genetic makeup most likely to alter a person’s response to medication.
Choice C rationale:
Excretion, or how the body eliminates a drug, can affect drug response, but it is not the aspect of genetic makeup most likely to alter this response.
Choice D rationale:
Metabolism, or how the body processes a drug, is the aspect of genetic makeup most likely to alter a person’s response to medication. Genetic differences can lead to variations in drug-metabolizing enzymes, affecting how quickly or slowly drugs are metabolized.