Diproson lotion contains a topical corticosteroid called betamethasone dipropionate, which is used in the treatment of skin conditions like eczema, psoriasis (red, itchy, sometimes scaly and thickened patches on the skin), contact dermatitis, seborrheic dermatitis (dandruff), lichen planus, (tiny red or purplish bumps on the skin, nails, scalp), lichen simplex (thickened and leathery skin), and otitis externa (redness and swelling in the outer ear canal)