Pustular psoriasis

Pustular psoriasis is a rare type of psoriasis that causes areas of pus-filled bumps or blisters on the skin. It can appear in smaller patches on the hands or feet or cover large parts of the body. The affected skin may appear pink, gray, purple or dark brown, depending on your skin color.

The skin may become swollen, sore and discolored shortly before blisters form, often within hours. The blisters usually heal within a few days but can come back. Triggers include infections, certain medicines and stopping some medicines too fast.

Small patches often are treated with steroid creams or ointments you can buy without a prescription. Larger areas may need treatment with prescription medicines taken by mouth or given as a shot. Light therapy may help after the blisters heal and the skin is less sensitive. Treating or avoiding triggers also can help the skin heal.