Mebendazole Dosing for 30 kg Teenage Boy
For a 30 kg teenage boy, administer mebendazole 100 mg twice daily for 3 days for most common intestinal helminth infections (ascariasis, hookworm, whipworm, pinworm). 1
Standard Dosing by Indication
The appropriate dose depends on the specific parasitic infection being treated:
Common Intestinal Nematodes
- Ascariasis, Hookworm, Trichuriasis (Whipworm): Mebendazole 100 mg twice daily for 3 days 1
Pinworm (Enterobius vermicularis)
- Single dose: 100 mg once, repeated in 2 weeks 2, 3
- This is the most straightforward regimen for pinworm
Visceral Larva Migrans (Toxocara)
- 100 mg twice daily for 3 days during the prepatent period, plus ivermectin 200 μg/kg once daily for 3 days 1
Important Clinical Considerations
Age and Safety
- The drug has not been extensively studied in children under 2 years 4
- At 30 kg, this teenage boy is well above the weight threshold for standard adult dosing
- The dose is NOT weight-based for standard helminth infections - it remains 100 mg twice daily regardless of whether the patient weighs 15 kg or 70 kg 1, 2, 1
Treatment Duration Matters
The 3-day course is critical for adequate efficacy. Research shows:
- Single-dose regimens have lower cure rates for hookworm (52.94%) and whipworm (75%) 5, 6
- The standard 3-day course achieves >85% cure rates for most nematode infections 7, 8
Common Pitfall to Avoid
Do not use weight-based dosing for standard helminth infections. The exception is high-dose mebendazole for hydatid disease (100-200 mg/kg/day), which is a completely different indication requiring specialist supervision 9. For routine intestinal worms, the fixed dose of 100 mg twice daily for 3 days applies universally.
Household Treatment
Consider treating all household members simultaneously, especially for pinworm infections, as reinfection rates are high even with effective medication 3. The short life span of adult pinworms and ease of transmission make this a practical necessity.
Monitoring
- No routine monitoring needed for standard 3-day courses 4
- Periodic assessment of liver and hematologic function advisable only during prolonged therapy (>3 days) 4
Side Effects
Mebendazole is generally well-tolerated. Mild diarrhea occurs in approximately 22% of children but is self-limiting 5. No serious adverse effects are expected at standard dosing 7, 8.