Which helminthic infection is primarily treated with praziquantel?

Praziquantel is primarily used in the treatment of schistosomiasis, which is caused by infection with parasitic flatworms known as schistosomes. This medication is particularly effective against various forms of schistosomiasis because it works by causing severe spasms and paralysis of the worms, leading to their dislodgment from the host's tissues and facilitating their elimination from the body.

While praziquantel can be used for some other helminthic infections, its hallmark effectiveness is with schistosomiasis. Other choices involve different classes of helminths. For instance, threadworms and roundworms are typically treated with agents such as mebendazole or ivermectin, while tapeworms may also require specific treatments like albendazole or other medications depending on the type of tapeworm. Thus, praziquantel's targeted action makes it the drug of choice for schistosomiasis.