Which parasite is commonly treated with albendazole or mebendazole for helminth infections?

• A. Taenia solium
• B. Giardia lamblia
• C. Ascaris lumbricoides
• D. Plasmodium falciparum

Answer: (C)

Albendazole and mebendazole are broad-spectrum anthelmintics that work by binding to parasite beta-tubulin and blocking microtubule formation, which disrupts nutrient uptake and kills many intestinal nematodes. This makes them a common first-line treatment for infections caused by nematodes such as Ascaris lumbricoides, the roundworm, which inhabits the intestines and is a classic target of these drugs in routine practice.

Giardia lamblia is a protozoan, not a helminth, and is typically treated with metronidazole or nitazoxanide rather than a benzimidazole. Plasmodium falciparum is the malaria parasite and requires antimalarial drugs, not helminth medications. Taenia solium is a cestode (tapeworm) and is usually treated with praziquantel (or niclosamide), though albendazole can be used in some cases but is not the standard first-line for tapeworm infection. Therefore, the organism most consistently treated with albendazole or mebendazole among these options is Ascaris lumbricoides.