Mebendazole Dosing for Ascariasis in a 14 kg Child
The prescribed regimen of mebendazole 7 mL (140 mg) twice daily for 3 days is INCORRECT and exceeds the recommended dose for this child—the correct dose is 100 mg (5 mL) twice daily for 3 days. 1, 2
Correct Dosing for Ascariasis
For a 14 kg child with ascariasis, administer mebendazole 100 mg (5 mL of the 100mg/5mL suspension) twice daily for 3 consecutive days. 1, 2
Alternative Dosing Options
The following regimens are equally effective for ascariasis treatment:
- Single dose of 500 mg mebendazole (25 mL of the suspension as a one-time dose) 1, 2
- Single dose of albendazole 400 mg as an alternative agent 1, 2
- Single dose of ivermectin 200 μg/kg (approximately 2.8 mg for this 14 kg child) 1
All three agents demonstrate high parasitological cure rates (>90%) and egg reduction rates (>96%) for ascariasis. 3
Why the Prescribed Dose is Problematic
The prescribed 7 mL dose delivers 140 mg per administration, which is 40% higher than the standard 100 mg dose. 2 While mebendazole has a favorable safety profile, there is no evidence that higher doses improve efficacy for ascariasis, and adhering to guideline-recommended dosing minimizes unnecessary drug exposure. 3, 4
Expected Treatment Outcomes
- Parasitological cure rate: 87-100% with standard dosing 3, 4
- Egg reduction rate: >99% by 14-60 days post-treatment 3, 5
- Efficacy is consistent across light and heavy infection intensities 4
Safety Considerations
Age Restrictions
- Do NOT administer mebendazole to infants under 12 months of age 2
- Do NOT administer to pregnant women 2
Administration
- Tablets should be chewed for optimal absorption 2
- Suspension can be taken with or without food
Adverse Events
Common but generally mild side effects include nausea, vomiting, abdominal pain, diarrhea, headache, and fever. 3 No serious adverse events have been reported in clinical trials. 3
Follow-Up and Re-treatment
- Re-treatment may be necessary in areas with high reinfection rates, particularly if the child has ongoing exposure to contaminated soil or poor sanitation 2
- Consider repeat stool examination 2-4 weeks after treatment if symptoms persist 6
- In endemic areas with continued exposure risk, preventive measures (handwashing, wearing shoes, avoiding unwashed produce) are essential 6
Clinical Context
Ascariasis is typically asymptomatic but can cause abdominal pain, diarrhea, and rarely gastrointestinal or biliary obstruction in children. 1 The child may pass visible earthworm-sized pink or white adult worms in stool. 1 Treatment is highly effective with any of the recommended single-agent regimens, and there is no evidence supporting combination therapy for uncomplicated ascariasis. 3