Can metoclopramide (intramuscular (IM) injection) be given to pediatric patients under 2 years?

Metoclopramide IM Injection in Pediatric Patients Under 2 Years

Metoclopramide should NOT be routinely administered via IM injection to pediatric patients below 2 years of age due to FDA contraindications, lack of established safety and efficacy, and high risk of serious adverse effects including extrapyramidal reactions. 1, 2

FDA Labeling and Regulatory Guidance

The FDA drug label explicitly states that "safety and effectiveness in pediatric patients have not been established" except for facilitating small bowel intubation. 2 Key FDA warnings include:

• Neonates are at particularly high risk due to prolonged drug clearance producing excessive serum concentrations and reduced NADH-cytochrome b5 reductase levels, making them more susceptible to methemoglobinemia 2
• The drug carries a black box warning from the FDA due to significant adverse effects in the pediatric population 1
• Extrapyramidal reactions are more common in pediatric patients than adults, with the safety profile in adults unable to be extrapolated to children 2

Clinical Evidence Against Use

Lack of Efficacy

• The American Academy of Pediatrics guidelines establish insufficient evidence to support routine use of metoclopramide in infants or older children with gastroesophageal reflux disease (GERD) 1
• A systematic review concluded the evidence level is "poor" with an "inconclusive" recommendation for safety and efficacy in infants, unable to support or oppose its use 3
• Meta-analysis of 7 randomized controlled trials in patients under 2 years with GERD showed symptom decrease but "clearly at the cost of significant adverse effects" 1

High Adverse Effect Profile

• Extrapyramidal reactions occur in 11-34% of pediatric patients, including somnolence, restlessness, and acute dystonic reactions 1, 4
• A systematic review of 108 studies found extrapyramidal symptoms in 9% (95% CI 5-17%), diarrhea in 6%, and sedation in 6% of children 5
• Dystonic reactions can occur even at recommended doses and may be misdiagnosed as encephalitis, tetany, or other conditions 4
• Rare but serious effects include dysrhythmia, respiratory distress/arrest, neuroleptic malignant syndrome, and tardive dyskinesia 5

Pharmacokinetic Concerns in Young Infants

In infants under 6 months with GERD receiving metoclopramide 0.15 mg/kg every 6 hours:

• Drug accumulation occurred with repeated dosing, with mean peak plasma concentrations 2-fold higher after the tenth dose compared to the first 2
• In the youngest patient (3.5 weeks), the half-life was significantly prolonged (23.1 hours after first dose, 10.3 hours after tenth dose) due to immature hepatic and renal systems 2
• This prolonged clearance creates risk for excessive drug accumulation in neonates 2

Recommended Alternatives

For pediatric GERD (if treatment is necessary):

• Dietary and postural modifications as first-line treatment 1
• Proton pump inhibitors (omeprazole, lansoprazole, esomeprazole) for patients ≥1 year with documented esophagitis 1
• Note: Randomized controlled trials with placebo in infants have not demonstrated superiority of proton pump inhibitors over placebo for reducing irritability 1

For chemotherapy-induced nausea and vomiting:

• 5-HT3 antagonists (ondansetron 5 mg/m² or 0.15 mg/kg, granisetron 0.01 mg/kg) combined with dexamethasone for high or moderate emetogenic potential chemotherapy 1

Exceptional Circumstances (If Metoclopramide Must Be Considered)

If metoclopramide is considered in truly exceptional circumstances despite the above warnings:

• Limit duration to less than 12 weeks 1
• Regular neurological monitoring for signs of extrapyramidal symptoms 1
• Avoid use in patients with seizure disorders (FDA contraindication) 1
• Exercise extreme caution in neonates given prolonged clearance and methemoglobinemia risk 2
• Consider that European and Canadian drug regulatory agencies have contraindicated use in children <1 year and caution against use in children <5 years 5

Common Pitfalls to Avoid

• Do not assume the IM route is safer than oral administration—the adverse effect profile remains problematic regardless of route 2, 5
• Do not confuse dystonic reactions with other neurological emergencies (encephalitis, tetany, seizures) 4
• Do not use in combination with MAO inhibitors, which can cause dangerous catecholamine release 2
• Do not overlook the need for insulin dose adjustment in diabetic patients, as metoclopramide affects gastric emptying and food delivery timing 2