Praziquantel is a broad-spectrum anthelmintic drug widely used to treat parasitic infections caused by schistosomes (blood flukes) and various tapeworms. Introduced in the late 1970s, it was developed through a collaboration between Bayer and Merck after extensive research into new antiparasitic agents. Praziquantel quickly became the drug of choice for schistosomiasis because of its high efficacy, safety, and single-dose convenience. Over the decades, it has played a major role in global public-health programs, particularly in endemic regions of Africa, Asia, and Latin America, significantly reducing the burden of parasitic diseases. Today, praziquantel remains an essential medicine on the WHO Model List and continues to be used extensively in mass drug-administration campaigns and routine clinical practice.
