Ivermectin is used to treat strongyloidiasis (threadworm; infection with a type of roundworm that enters the body through the skin, moves through the airways and lives in the intestines). Ivermectin is also used to control onchocerciasis (river blindness; infection with a type of roundworm that may cause rash, bumps under the skin, and vision problems including vision loss or blindness). Ivermectin is in a class of medications called anthelmintics.