Which therapy is commonly used for nematode infections such as Ascaris, hookworms, and whipworm?

• A. Albendazole or mebendazole; combination therapy may be used in some settings.
• B. Praziquantel
• C. Metronidazole
• D. Ivermectin

Answer: (A)

For nematode infections like Ascaris, hookworms, and whipworm, the first-line therapy is a benzimidazole class drug, such as albendazole or mebendazole. These medications work by inhibiting the parasite’s ability to digest sugars—they bind to nematode beta-tubulin, disrupting microtubule formation, which blocks glucose uptake and leads to immobilization and death of the worm. They are broad-spectrum against soil-transmitted helminths and are favored for their effectiveness, safety, and practicality (often given in a single dose, which is ideal for mass treatment programs).

Praziquantel targets flatworms like flukes and tapeworms, not the common soil-transmitted nematodes. Metronidazole is used against certain protozoa and anaerobic bacteria, not helminths. Ivermectin can treat some other nematode infections (like Strongyloides and certain filarial infections) but is not the standard first-line therapy for these three soil-transmitted nematodes. In some settings, combination therapy may be used to enhance cure rates or address co-infections, but albendazole or mebendazole remains the primary treatment.