Rhode Island Multistate Pharmacy Jurisprudence (MPJE) Practice Exam

Which of the following drugs is known to be a common narrow therapeutic range medication?

1. Paracetamol

2. Levothyroxine

3. Amoxicillin

4. Sertraline

The correct answer is: Levothyroxine

Levothyroxine is indeed recognized as a medication that has a narrow therapeutic range. This means that the difference between the minimum effective dose and the minimum toxic dose is small, necessitating careful monitoring of serum levels to ensure efficacy and avoid toxicity. Given that levothyroxine is a thyroid hormone replacement therapy, its dosage must be tailored to meet individual patient needs, and even small variations in dosage can lead to significant clinical effects, either resulting in an underactive or overactive thyroid condition. In contrast, while paracetamol, amoxicillin, and sertraline are important medications, they do not have the same level of concern regarding a narrow therapeutic range. Paracetamol has a wider therapeutic index, meaning it is generally safe at a broader range of doses. Amoxicillin, an antibiotic, is also well-tolerated across a wider dosing range without toxicity issues arising at commonly prescribed doses. Sertraline, an antidepressant, does require monitoring for therapeutic response and potential side effects, but it does not typically present the same risks associated with specific dosage adjustments that characterize narrow therapeutic range drugs like levothyroxine. Understanding these distinctions is crucial in the practice of pharmacy, as medications with narrow therapeutic ranges require greater diligence in monitoring and