An anti-parasiticidal composition presented as a topical "pour-on" product fortreating animals infected by parasites which are known to be susceptible tosalicylanilides, especially closantel, alone or together with at least oneother anti~ parasitic compound of the avermectin or milbemycin type and offersenhanced bioavailability of the salicylanilide by provision of a deliverysystem comprising at least 20%(v/v) of one or more alcohols, and optionallyincluding a polymeric moiety selected from the group consisting ofpolyvinylpyrrolidone (PVP), polyoxypropylene/polyoxyethylene block copolymers(poloxamer), and polyethylene glycols (PEG), thereby improving thebioavailability of e.g. closantel (as assessed with respect to blood plasmalevels of closantel).
