NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

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Ace your North American Pharmacist Licensure Examination (NAPLEX) with our comprehensive practice test. Features include interactive flashcards, multiple-choice questions, with detailed hints and explanations. Fast-track your pharmacy career today!

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Select a drug that induces CYP-2C9.

  1. Ritonavir

  2. Carbamazepine

  3. Erythromycin

  4. Tacrolimus

The correct answer is: Carbamazepine

Carbamazepine is the correct answer because it is a known inducer of CYP-2C9. Inducers of CYP-2C9 can increase the activity of this enzyme, leading to the accelerated metabolism of drugs that are substrates for CYP-2C9. This can result in decreased drug concentrations and potentially reduced efficacy of other medications that are metabolized by CYP-2C9. The other options: A. Ritonavir - Ritonavir is actually known as a potent inhibitor of CYP-2C9, rather than an inducer. C. Erythromycin - Erythromycin is not a known inducer of CYP-2C9; instead, it is more commonly associated with inhibiting CYP-3A4. D. Tacrolimus - Tacrolimus is not a drug that induces CYP-2C9; it is primarily metabolized by CYP-3A4.