Zimecterin Gold provides effective treatment and control of the following parasites in horses: tapeworms, large strongyles, small strongyles, pinworms, roundworms (ascarids), hairworms, large-mouth stomach worms, bots, lungworms, intestinal threadworms, and summer sores. Zimecterin Gold kills important internal parasites, including bots and the arterial stages of S. vulgaris, with a single dose.