Ivermectin is a medication that is effective against many types of parasites. It is used to treat head lice, scabies, river blindness, strongyloidiasis, and lymphatic filariasis, among others. It can be either applied to the skin or taken by mouth. The eyes should be avoided. Common side effects include red eyes, dry skin, and burning skin. It is in the avermectin family of medications, which work by causing the membrane of invertebrate nerve and muscle cells to become more permeable to chloride ions, resulting in paralysis and death. It is used to treat rosacea.