American Board of Internal Medicine (ABIM) Certification Practice Exam

What is the recommended initial dosage of metoclopramide for treating gastroparesis?

1. 10 mg once daily

2. 20 mg twice daily

3. 5 mg three times daily

4. 15 mg four times daily

The correct answer is: 5 mg three times daily

The recommended initial dosage of metoclopramide for treating gastroparesis is 5 mg three times daily. This dosage is based on the need to manage symptoms effectively while minimizing potential side effects associated with higher doses. Metoclopramide works by enhancing gastrointestinal motility and increasing gastric emptying, which is particularly beneficial in patients with gastroparesis, where delayed gastric emptying is a significant concern. Starting with a lower dose of 5 mg allows for a gradual approach to therapy, enabling healthcare providers to assess the patient’s response and tolerance to the medication. The frequency of administration (three times daily) also plays a crucial role in maintaining therapeutic levels in the body, thus improving symptom control throughout the day. Additionally, this dosing schedule aligns with clinical recommendations that suggest more frequent dosing for medications with a short half-life, like metoclopramide, to ensure consistent plasma levels and effective symptom relief. In higher doses or less frequent dosing, there may be an increased risk of adverse effects, which can de-incentivize patient compliance. Thus, the initial dosage aims to provide a balance between efficacy and safety.