NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

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Prepare for the NAPLEX (North American Pharmacist Licensure Examination) Test. Study with flashcards and multiple choice questions, each question has hints and explanations. Get ready for your exam!

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Which medication is a CYP-2D6 substrate?

  1. Paroxetine

  2. Methadone

  3. Amiodarone

  4. Esomeprazole

The correct answer is: Methadone

Methadone is the correct answer because it is known to be a substrate of the CYP-2D6 enzyme. Paroxetine, Amiodarone, and Esomeprazole are not known to be substrates of this specific enzyme. Paroxetine is metabolized by CYP-2C19, Amiodarone by CYP-3A4, and Esomeprazole by CYP-2C19 and CYP-3A4. While some medications may be metabolized by multiple enzymes, only Methadone is widely recognized and studied as a CYP-2D6 substrate.