Toxicological profile of praziquantel, a new drug against cestode and schistosome infections, as compared to some other schistosomicides.

2-Cyclohexylcarbonyl-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a] isoquinolin-4-one (praziquantel, EMBAY 8440, Biltricide), a new anthelminthic drug with activity against all species of schistosomes pathogenic to man, and against a wide range of cestodes, did not reveal any undesired pharmacodynamic effects. After oral administration praziquantel is quantitatively and rapidly absorbed, metabolized and excreted as a variety of metabolites predominantly via the kidneys by all species tested, including man. Its acute toxicity tested in rats, mice, rabbits and dogs is very low as compared with other schistosomicidal drugs.