Hydrocortisone is a topical steroid. It reduces the actions of chemicals in the body that cause inflammation, redness, and swelling. Hydrocortisone topical is used to treat inflammation of the skin caused by a number of conditions such as allergic reactions, eczema, or psoriasis. Hydrocortisone topical may also be used for other purposes not listed in this medication guide.Hydrocortisone is a topical steroid. It reduces the actions of chemicals in the body that cause inflammation, redness, and swelling.