What is the recommended dosing for Reglan (Metoclopramide) in the treatment of gastroparesis?

Metoclopramide Dosing for Gastroparesis

For gastroparesis, metoclopramide should be dosed at 10 mg orally, 30 minutes before meals and at bedtime (QID) for a maximum duration of 12 weeks due to risk of tardive dyskinesia. 1, 2

Standard Dosing Regimen

• First-line dosing: 10 mg orally, 30 minutes before meals and at bedtime (QID) 1, 2
• Maximum duration: Limited to 12 weeks of continuous use due to risk of tardive dyskinesia 1
• Alternative administration: If severe symptoms are present, therapy may begin with metoclopramide injection (IM or IV) before transitioning to oral administration 2

Dosing Adjustments

• Renal impairment: For patients with creatinine clearance below 40 mL/min, start at approximately half the recommended dose (5 mg QID) 2
• Elderly patients: Consider lower starting doses due to increased risk of tardive dyskinesia 3
• Route considerations: Metoclopramide nasal spray may be effective in female patients with diabetes and gastroparesis who have significant nausea/vomiting 4

Efficacy and Monitoring

• Metoclopramide accelerates gastric emptying and can significantly reduce symptoms of gastroparesis, with an overall mean symptom reduction of 52.6% compared to placebo 5
• Monitor for symptom improvement within 1-2 weeks of initiating therapy
• Regular assessment for neurological side effects is essential, particularly for tardive dyskinesia

Important Considerations and Cautions

• Risk of tardive dyskinesia: The risk is approximately 0.1% per 1000 patient-years, which is lower than previously estimated 1-10% 3

• High-risk groups for tardive dyskinesia:

  • Elderly females
  • Diabetic patients
  • Patients with liver or kidney failure
  • Patients on concomitant antipsychotic therapy 3

• Tachyphylaxis: Some patients may develop tolerance to metoclopramide's prokinetic effects with chronic use 6

• Gender differences: Metoclopramide nasal spray has shown better efficacy in women than men with diabetic gastroparesis 4

Alternative Medications When Metoclopramide Is Contraindicated

• Erythromycin: 40-250 mg orally three times daily (alternative prokinetic) 1
• Antiemetics for symptom control:
  • Ondansetron: 4-8 mg 2-3 times daily
  • Prochlorperazine: 5-10 mg four times daily
  • Trimethobenzamide: 300 mg three times daily 7, 1

Remember that metoclopramide is the only FDA-approved medication specifically for gastroparesis, and its use should be carefully monitored due to the risk of neurological side effects.