are named after a German dermatologist, Paul Gerson Unna. Unna Boots are typically used to treat edema, ulcers and sores. They are used sometimes with a Hydrogel dressing. Unna Boots may be worn up to 7 days, without changing, if medical conditions permit. Unna Boots are a compression bandages that are embedded with zinc oxide, which helps relieve skin irritation and keep the wound area stay moist. As the Unna Boot dries, it forms a semi-rigid cast, providing support.