 The drugs of choice for soil-transmitted helminths are mebendazole and albendazole; for schistosomiasis and tapeworms it is and praziquantel.Antiparasitics that specifically target worms of the genus "Ascaris" are called ascaricides.The ability of parasites to survive treatments that are generally effective at the recommended doses is a major threat to the future control of worm parasites in small ruminants and horses.