A new antifungal medication is being tested in Phase I clinical trials. Examination of the pharmacokinetic propeies of the drug reveals that the half-life of the drug is 6 hours. If a continuous intravenous infusion of this drug were staed on a research subject, how long would it take to reach 75% of steady state?
Correct Answer: 12
Description: The rule of thumb is that the plasma concentration will reach 50% in one half-life, 75% in two half-lives, 87.5% in three half-lives, etc., so that the difference between the current drug level and 100% halves with each half-life. In this instance, it takes two half-lives to reach 75%. The half-live of this drug is 6 hours, so two half-lives is 12 hours. Ref: Buxton I.L., Benet L.Z. (2011). Chapter 2. Pharmacokinetics: The Dynamics of Drug Absorption, Distribution, Metabolism, and Elimination. In L.L. Brunton, B.A. Chabner, B.C. Knollmann (Eds), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.
Category:
Pharmacology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now