Which drug is used to treat Schistosomiasis?

• A. Albendazole
• B. Praziquantel
• C. Ivermectin
• D. Mebendazole

Answer: (B)

Praziquantel is used to treat schistosomiasis because it is highly effective against the adult flukes that cause the disease and has a strong track record of cure with a favorable safety profile. Its action is to disrupt the parasite’s tegument and increase calcium permeability, causing rapid parasite paralysis and detachment from the venous sites where Schistosoma dwells. This makes them more vulnerable to immune clearance and excretion in the urine or stool.

Praziquantel works across the main Schistosoma species seen in humans, which is why it is the standard therapy. It’s particularly important to note that it targets the adult worms well, and there can be some concern about immature stages, which is why treatment may be repeated in certain settings or timed with testing in endemic areas.

Other common antiparasitics target different parasites. Albendazole and mebendazole are primarily used for nematodes (roundworms) and are not reliably effective against schistosomes. Ivermectin is effective against many nematodes and some arthropods but does not reliably treat schistosomiasis.