Despite its name, ringworm is not a worm. It's a condition caused by a fungal infection under the surface of the skin, and it's highly treatable with antiseptics such as topical iodine. Iodine applied to a ringworm site kills the fungus through skin absorption. Iodine should not be ingested, and adults should closely supervise the use of iodine on children.
Cleanse the ringworm site and surrounding skin thoroughly to remove any bacteria and dead skin cells. Use a mild skin cleanser or antibacterial soap, then pat dry with a clean towel. No one else should use the towel, as ringworm is highly contagious. Towels used during treatment should be bleached afterward.
Apply a small amount of 7 percent iodine tincture to a cotton ball. Avoid contact with clothing and other areas of the skin, as iodine will stain. Rub the iodine into the affected skin until the skin is thoroughly saturated. The skin will absorb the iodine, which in turn will kill the fungus. You can apply iodine up to three times daily until the ringworm has disappeared.
Apply a bandage large enough to cover the entire ringworm site. This will prevent iodine transfer and keep the ringworm fungus from spreading to other parts of the body or to other people through physical contact. You may keep the bandage off while at home, being careful to prevent spreading the fungus, but when you're in public, the area ideally should be bandaged.