Question

"The client has a diagnosis of multiple sclerosis and is taking the drug interferon beta-1a (Rebif)." The client takes this drug by subcutaneous injection three times a week. The dosage is 44 mcg/injection. If the client takes an injection on Monday, how many mcg of the drug would still be in the client's system when she takes her next injection on Wednesday, assuming the half-life of the drug is 24 hours? Answer using numbers only (no units).

Answer 1

11

Step-by-step explanation:

The half-life of a drug is the time it takes for the concentration of that substance to fall to half of its initial value. Since the half-life of Rebif is 24 hs, and the time between injections is 48 hs, two half-lives passed. Therefore, a quarter of the initial dosage will remain on client´s system (11 mcg).