What is the recommended dose of metoclopramide (antiemetic agent) rectal suppository for adults?

Metoclopramide Rectal Suppository Dosage for Adults

The recommended dose of metoclopramide rectal suppository for adults is 20 mg per dose. 1, 2

Dosing Information

• The standard rectal suppository formulation of metoclopramide contains 20 mg of the active drug 1
• Rectal administration provides comparable bioavailability to other routes of administration, with studies showing effective drug delivery via this route 1
• For treatment of nausea and vomiting, a single 20 mg rectal suppository can provide sustained release effects, potentially reducing the need for multiple daily doses 2

Clinical Applications

• Metoclopramide is primarily used as an antiemetic agent for various conditions including:

  • Opioid-induced nausea and vomiting 3
  • Chemotherapy-induced nausea and vomiting 3
  • Radiation therapy-induced nausea and vomiting 3
  • Postoperative nausea and vomiting 4

• For persistent nausea related to cancer pain management, metoclopramide 10-20 mg PO is recommended several times daily 3

Administration Considerations

• Rectal administration is particularly useful when oral administration is not feasible due to:

  • Severe vomiting 5
  • Inability to tolerate oral medications 2
  • Need for rapid symptom control 1

• When using metoclopramide as an adjunctive therapy for nausea management, it can be administered:

  • As a prophylactic treatment for patients with prior history of opioid-induced nausea 3
  • As rescue therapy for breakthrough nausea and vomiting during radiation therapy 3

Important Precautions

• Limit use to short-term therapy when possible, as extended use increases risk of adverse effects 4
• Monitor for extrapyramidal symptoms, which can occur rarely but are more common with high doses or prolonged use 4, 5
• Common adverse reactions include restlessness, drowsiness, fatigue, and lassitude 4
• In rare cases, even short-term, low-dose treatment can cause long-lasting adverse effects including involuntary movements 5

Alternative Considerations

• For patients who cannot tolerate metoclopramide or have contraindications:
  • Prochlorperazine 5-10 mg can be considered as an alternative 3
  • Haloperidol 0.5-1 mg may be effective for opioid-induced nausea 3
  • Serotonin antagonists (e.g., ondansetron) can be added for persistent nausea 3

Remember that metoclopramide works through both central (dopamine antagonism) and peripheral (prokinetic) mechanisms, making it particularly effective for many types of nausea and vomiting 4.