Question

If a client takes 40mg of a drug with a half-life of 2 hours, how much of the drug will remain hours after administration?

Answer 1

After 3 half-lives (6 hours), the amount of drug remaining from an initial 40mg dose, with each half-life being 2 hours, would be 5mg.

Step-by-step explanation:

If a client takes 40mg of a drug with a half-life of 2 hours, the amount of drug remaining after each half-life has passed decreases by half. To calculate the amount of drug left after a certain number of hours, we use the formula:

• Remaining amount = Initial amount × (½)^(Number of half-lives passed)

Given that the half-life of the drug is 2 hours, after 6 hours have passed, this represents 3 half-lives (since 6 / 2 = 3). Now we can determine how much of the drug is left:

Remaining amount = 40mg × (½)^3

Remaining amount = 40mg × 1/8

Remaining amount = 5mg