What is the recommended dose of metoclopramide (antiemetic medication) for children?

Metoclopramide Dosing in Pediatric Patients

The recommended dose of metoclopramide in children is 0.1 mg/kg per dose, with specific age-based adjustments: 0.1 mg/kg for children under 6 years, 2.5-5 mg for ages 6-14 years, and 10 mg for children over 14 years. 1, 2

Standard Dosing by Age and Indication

For Antiemetic Use (Postoperative Nausea/Vomiting)

• Children under 6 years: 0.1 mg/kg per dose 1, 2
• Children 6-14 years: 2.5-5 mg per dose 2
• Children over 14 years and adults: 10 mg per dose 2
• Maximum frequency: Not to be combined with tramadol; contraindicated if <1 year old 1

For Chemotherapy-Induced Nausea and Vomiting

• High-dose regimen: 1-2 mg/kg per dose IV, administered slowly over 15 minutes 1, 2
• Timing: Given 30 minutes before chemotherapy, repeated every 2 hours for two doses, then every 3 hours for three doses 2
• Highly emetogenic drugs (cisplatin, dacarbazine): Use 2 mg/kg per dose 2
• Less emetogenic regimens: 1 mg/kg per dose may be adequate 2

For Gastrointestinal Procedures (Small Bowel Intubation)

• Children under 6 years: 0.1 mg/kg as single dose IV over 1-2 minutes 2
• Children 6-14 years: 2.5-5 mg as single dose 2
• Children over 14 years: 10 mg as single dose 2

Critical Safety Considerations

Extrapyramidal Symptom Risk

The primary concern with metoclopramide in children is the high incidence of extrapyramidal reactions (EPS), which occurs in 9-25% of pediatric patients even at recommended doses 3, 4. This risk is substantially higher than in adults and represents the most significant limitation of this medication in children.

Key risk factors for EPS include:

• Higher doses (≥2 mg/kg): 15% developed EPRs and 33% developed akathisia at doses ≥2 mg/kg 5
• Consecutive day dosing: Children receiving two consecutive days of treatment had higher frequency of EPRs 5
• Younger age: Children are more susceptible than adults to dystonic reactions 3, 6

Management of Acute Dystonic Reactions

If acute dystonic reactions occur, immediately administer diphenhydramine 1-2 mg/kg (or 25-50 mg/dose) parenterally 7. The FDA label specifies 50 mg Benadryl (diphenhydramine hydrochloride) intramuscularly, with symptoms usually subsiding rapidly 2. These reactions are reversible and resolve quickly with treatment 4.

Dosing Adjustments for Special Populations

Renal Impairment

For patients with creatinine clearance below 40 mL/min, initiate therapy at approximately one-half the recommended dosage 2. The dose may be increased or decreased based on clinical efficacy and safety, as metoclopramide is excreted principally through the kidneys 2.

Hepatic Impairment

Metoclopramide undergoes minimal hepatic metabolism except for simple conjugation, and its safe use has been described in patients with advanced liver disease whose renal function was normal 2.

Regulatory Restrictions and Contraindications

Important regulatory warnings:

• Contraindicated in children <1 year of age 1, 4
• Use with caution in children <5 years of age 4
• Duration should not exceed 5 days 4
• Do not combine with tramadol 1

These restrictions were implemented by Canadian and EU drug regulatory agencies based on safety concerns 4.

Clinical Rounding Tolerance

Despite the risk of dose-dependent tardive dyskinesia, metoclopramide is often rounded more aggressively in clinical practice, with a rounding tolerance of 10% considered acceptable by expert consensus 1. This reflects the balance between avoiding adverse effects and achieving practical dosing in real-world settings 1.

Administration Considerations

• IV administration: Should be given slowly over 1-2 minutes for single doses, or over at least 15 minutes for chemotherapy-related dosing 2
• Prophylactic diphenhydramine: Consider concurrent administration to reduce EPR incidence, particularly with higher doses or consecutive day dosing 5, 8
• Monitoring: Close observation for dystonic reactions, sedation (6% incidence), and diarrhea (6% incidence) is essential 4