A nurse is preparing to administer levothyroxine 100 mcg PO to a client who has hypothyroidism.

Available is levothyroxine 50 mcg 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:
One-eighth to one-fourth of the normal adult dose is not typically used when initiating drug therapy in elderly adults. This range might be too low to be effective.
Choice B rationale:
One-fourth to one-third of the normal adult dose is also not typically used when initiating drug therapy in elderly adults. This range might still be too low to be effective.
Choice C rationale:
One-half to three-fourths of the normal adult dose is not typically used when initiating drug therapy in elderly adults. This range might be too high and increase the risk of adverse effects.
Choice D rationale:
One-third to one-half of the normal adult dose is used when initiating drug therapy in elderly adults. This range is appropriate to balance efficacy and safety.

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.