Betamethasone is a synthetic corticosteroid that is used to treat a variety of conditions, such as inflammation, allergic reactions, and autoimmune disorders. It works by decreasing inflammation and suppressing the immune system. Betamethasone is available in various forms, including creams, ointments, lotions, solutions, and injectable formulations. It is also available as a nasal spray and as an oral tablet or syrup. Some of the common conditions that betamethasone is used to treat include eczema, psoriasis, asthma, rheumatoid arthritis, and inflammatory bowel disease. It should be used only under the direction and supervision of a healthcare professional.