Most anthelmintics generally have a wide margin of safety, considerable activity against immature (larval) and mature stages of helminths, and a broad spectrum of activity.

 

There are several classes of anthelmintics, eg, benzimidazoles and probenzimidazoles, salicylanilides and substituted phenols, imidazothiazoles, tetrahydropyrimidines, organophosphates, and macrocyclic lactones. Although it may be thought that chemotherapeutic control of helminth infections is currently satisfactory, selection for parasite resistance should always be a concern.