What is the recommended dose of albendazole (anti-parasitic medication) for treating ascaris (roundworm) infection?

Albendazole Dose for Ascaris

For ascariasis (roundworm infection), the recommended dose is albendazole 400 mg as a single oral dose. 1, 2

Standard Dosing Regimen

• Albendazole 400 mg as a single oral dose is the established treatment for Ascaris lumbricoides infection in both adults and children. 1, 2
• This single-dose regimen achieves 100% cure rates for ascariasis at 14 and 21 days post-treatment. 3
• The same 400 mg dose applies across all age groups, including children as young as 2 years old. 2, 4

Clinical Efficacy

• The 400 mg single dose demonstrates superior effectiveness specifically for Ascaris compared to other intestinal helminths, with consistently high cure rates (86.7-100%) across multiple studies. 3, 5, 6
• Egg reduction rates reach 100% at all dose levels (400 mg, 600 mg, 800 mg) for Ascaris, making the lower 400 mg dose optimal. 3
• Research confirms that albendazole 400 mg single dose is highly effective against Ascaris lumbricoides, Ancylostoma duodenale, and Enterobius vermicularis. 6

Important Clinical Considerations

When to Consider Empirical Treatment

• For asymptomatic eosinophilia with negative stool microscopy in travelers/migrants from endemic areas, consider empirical treatment with albendazole 400 mg plus ivermectin 200 μg/kg (single dose) to cover possible prepatent or undetected geohelminth infections. 1, 2
• Always exclude Loa loa infection in people who have traveled to endemic regions BEFORE administering ivermectin. 1, 2

Pediatric Dosing

• Children over 24 months: albendazole 400 mg single dose (same as adults). 1, 2
• Children aged 12-24 months: discuss with an expert before treatment. 1, 2

Clinical Presentation to Recognize

• Ascariasis may present with nausea, vomiting, diarrhea, and abdominal pain. 1
• Heavy infections can result in anemia, particularly in young children. 1
• Diagnosis is confirmed by concentrated stool microscopy. 1

Common Pitfalls to Avoid

• Do not use prolonged courses for simple ascariasis - a single 400 mg dose is sufficient and avoids unnecessary monitoring for hepatotoxicity and leukopenia that becomes necessary with treatment exceeding 14 days. 7
• Do not confuse dosing for different parasites - while Ascaris requires only a single 400 mg dose, other helminths like Trichuris (whipworm) may require higher doses (600 mg) or multiple-day regimens. 3
• The drug is well-tolerated with minimal side effects at the 400 mg single-dose level. 3, 6