Nausea and Vomiting in Infants and Children – Pediatrics – Merck Manuals Professional Edition

Drugs frequently used in adults to decrease nausea and vomiting are used less often in children because the usefulness of treatment has not been proved and because these drugs have potential risks of adverse effects and of masking an underlying condition. However, if nausea or vomiting is severe or unremitting, antiemetic drugs can be used cautiously in children > 2 years. Useful drugs include

Ondansetron: 0.15 mg/kg (maximum 8 mg) IV every 8 hours or, if the oral form is used, for children 2 to 4 years, 2 mg every 8 hours; for those 4 to 11 years, 4 mg every 8 hours; for those ≥ 12 years, 8 mg every 8 hours

Prochlorperazine: For children > 2 years and weighing 9 to 13 kg, 2.5 mg orally every 12 to 24 hours; for those 13 to 18 kg, 2.5 mg orally every 8 to 12 hours; for those 18 to 39 kg, 2.5 mg orally every 8 hours; for those > 39 kg, 5 to 10 mg orally every 6 to 8 hours

Promethazine is an H1 receptor blocker (antihistamine) that inhibits the emetic center response to peripheral stimulants. The most common adverse effects are respiratory depression, sedation, dizziness, anxiety, blurred vision, dry mouth, impotence, and constipation; the drug is contraindicated in children < 2 years. Therapeutic doses of promethazine can cause extrapyramidal adverse effects, including torticollis.

Ondansetron is a selective serotonin (5-HT3) receptor blocker that inhibits the initiation of the vomiting reflex in the periphery. A single dose of ondansetron is safe and effective in children who have acute gastroenteritis and are unable to tolerate oral rehydration therapy Oral Rehydration Oral fluid therapy is effective, safe, convenient, and inexpensive compared with IV therapy. Oral fluid therapy is recommended by the American Academy of Pediatrics and the World Health Organization… read more (ORT). By facilitating ORT, this drug may prevent the need for IV fluids or, in children given IV fluids, may help prevent hospitalization. Typically, only a single dose is used because repeated doses can cause persistent diarrhea. Other common adverse effects include headache, dizziness, drowsiness, blurred vision, constipation, muscle stiffness, tachycardia, and hallucinations.