What are the guidelines for deworming in children and adults, including recommended medications, dosages, and treatment duration?

Deworming Guidelines for Children and Adults

Children: Recommended Approach

For routine preventive deworming in endemic areas, administer albendazole 400 mg as a single oral dose every 6 months to all children over 24 months of age, with treatment repeated at 8 weeks for schistosomiasis-endemic regions. 1

Dosing by Age Group

Children ≥24 months:

• Albendazole 400 mg single dose OR Mebendazole 500 mg single dose for soil-transmitted helminths (ascariasis, hookworm, trichuriasis) 1, 2
• For empirical treatment with suspected strongyloidiasis: Add ivermectin 200 μg/kg single dose (must exclude Loa loa exposure before ivermectin administration) 1
• Repeat treatment at 8 weeks if schistosomiasis is suspected, as eggs and immature forms are resistant to initial treatment 1

Children 12-24 months:

• Requires expert consultation before treatment 1
• Standard albendazole 400 mg may be used but discuss with specialist first

Children <12 months:

• Not routinely recommended in standard deworming programs 1

Treatment Duration by Infection Type

Single-dose therapy (most common):

• Pinworm (Enterobius): 1 tablet once; repeat if not cured after 3 weeks 2
• Ascariasis, Trichuriasis, Hookworm: Mebendazole 500 mg twice daily for 3 consecutive days 2
• Schistosomiasis: Praziquantel 25 mg/kg three times daily for 2-3 consecutive days 1

Extended therapy (specific infections):

• Cutaneous larva migrans: Albendazole 400 mg twice daily for 21 days 1
• Echinococcosis: Requires specialist management 1
• Fascioliasis: Triclabendazole 10 mg/kg once daily for 2 days 1

Critical Caveats for Pediatric Deworming

• Take with food: Albendazole absorption increases up to 5-fold when administered with fatty meals (approximately 40 grams fat content) 3
• Tablets may be crushed: For children unable to swallow whole tablets, crush and mix with food 2, 3
• Geographic considerations: Must exclude Loa loa in children who traveled to endemic regions (Central/West Africa) before administering ivermectin to prevent severe adverse reactions 1
• Treatment efficacy varies: Single-dose albendazole shows high cure rates for Ascaris (91-97%) but lower rates for Trichuris (27-51%) 4, 5, 6

When Triple-Dose Regimens Are Warranted

For persistent Trichuris trichiura infections:

• Albendazole 400 mg daily for 3 consecutive days achieves 92% cure rate versus 69% with single dose 4
• Mebendazole 500 mg daily for 3 consecutive days achieves 71% cure rate versus 29% with single dose 4
• Alternative for treatment failures: Albendazole 400 mg plus ivermectin 600 μg single doses combined achieves 75% cure rate for Trichuris 5

Adults: Recommended Approach

Adults should receive the same dosing as children for routine deworming: albendazole 400 mg single dose or mebendazole 500 mg single dose, with treatment frequency based on endemic risk. 1, 2

Standard Adult Dosing

Soil-transmitted helminths:

• Albendazole 400 mg single dose OR Mebendazole 500 mg single dose OR Ivermectin 200 μg/kg single dose 1
• Maximum daily dose: 4 grams amoxicillin equivalent (not applicable to albendazole/mebendazole which have fixed dosing) 7

Schistosomiasis:

• Praziquantel 25 mg/kg three times daily for 2-3 consecutive days 1
• Alternative: Praziquantel 40 mg/kg single dose for Schistosoma mansoni and S. haematobium 1

Tapeworm infections:

• Praziquantel 40 mg/kg single dose for intestinal Taenia species 1
• Praziquantel 60 mg/kg in two divided doses for other cestode infections 1

Fascioliasis:

• Triclabendazole 10 mg/kg once daily for 2 days (note: increasing resistance reported) 1

Treatment Frequency

Endemic areas with >20% prevalence:

• Biannual treatment (every 6 months) recommended by WHO for preventive chemotherapy programs 8, 9
• Mexico's national program administers deworming approximately every 8 months through health weeks 9

Post-treatment monitoring:

• Reassess 2-4 weeks after treatment for persistent infections 8, 5
• If infection persists at 3 weeks, administer second course 2
• For schistosomiasis, repeat at 8 weeks to treat residual worms that matured after initial treatment 1

Important Adult-Specific Considerations

• Pregnancy: Albendazole is contraindicated; advise pregnant women of fetal risks 3
• HIV infection: Same dosing applies, though helminth co-infection is common cause of eosinophilia in HIV-positive patients 1
• Immunocompromised patients: Seek expert advice, particularly for strongyloidiasis which can cause hyperinfection syndrome 1

Common Pitfalls to Avoid

1. Inadequate treatment of Trichuris: Single-dose therapy has only 27-51% cure rates; consider triple-dose regimens or combination therapy for moderate-to-heavy infections 4, 5, 6

2. Forgetting repeat dosing for schistosomiasis: Immature forms resist treatment; 8-week repeat is essential 1

3. Administering ivermectin without screening for Loa loa: Can cause fatal encephalopathy in co-infected patients 1

4. Fasting administration: Significantly reduces albendazole absorption; always give with fatty meal 3

5. Assuming single-dose cures all infections: Efficacy varies dramatically by species—Ascaris 93-97%, Trichuris 27-51%, hookworm 78-92% 4, 5, 6