A nurse is preparing to administer levothyroxine 0.275 mg PO daily. The medication is available as 137 mcg tablets. How many tablets should be administered?

A nurse is preparing to administer levothyroxine 0.275 mg PO daily. The medication is available as 137 mcg tablets. How many tablets should be administered?

• A. 1 tablet
• B. 2 tablets
• C. 2.5 tablets
• D. 3 tablets

Answer: (B)

You start by getting the doses in the same unit. The prescription is 0.275 mg, which equals 275 mcg. Each tablet is 137 mcg. Divide the total micrograms by the tablet strength: 275 ÷ 137 ≈ 2.01 tablets. Since you typically administer whole tablets, two tablets is the closest practical dose. Two tablets provide 274 mcg, which is only about 1 mcg (0.36%) different from the exact 275 mcg. One tablet would be far under the dose, while 2.5 or 3 tablets would be far too high. So, two tablets is the best match.

You start by getting the doses in the same unit. The prescription is 0.275 mg, which equals 275 mcg. Each tablet is 137 mcg. Divide the total micrograms by the tablet strength: 275 ÷ 137 ≈ 2.01 tablets. Since you typically administer whole tablets, two tablets is the closest practical dose. Two tablets provide 274 mcg, which is only about 1 mcg (0.36%) different from the exact 275 mcg. One tablet would be far under the dose, while 2.5 or 3 tablets would be far too high. So, two tablets is the best match.