Ivermectin is used to control skin parasites, gastrointestinal parasites and parasites within the bloodstream in dogs and cats. Parasitic diseases are common in animals'. Parasites can affect the skin, ears, stomach and intestines, and the internal organs including the heart,lung and liver. Several drugs have been developed to kill or prevent parasites such as fleas,ticks, mites and worms. Ivermectin and related drugs are among the most effective of these.