Praziquantel

Praziquantel, sold under the brandname Biltricide among others, is a medication used to treat a number of types of parasitic worm infections in mammals, birds, amphibians, reptiles, and fish. In humans specifically, it is used to treat schistosomiasis, clonorchiasis, opisthorchiasis, tapeworm infections, cysticercosis, echinococcosis, paragonimiasis, fasciolopsiasis, and fasciolosis. It should not be used for worm infections of the eye. It is taken by mouth. Side effects in humans may include poor coordination, abdominal pain, vomiting, headache, and allergic reactions. While it may be used during pregnancy, it is not recommended for use during breastfeeding. Praziquantel is in the anthelmintic class of medications. It works partly by affecting the function of the worm's sucker. Praziquantel was approved for medical use in the United States in 1982, and in the European Union in April 2025. It is on the World Health Organization's List of Essential Medicines.