Betamethasone is a topical steroid that reduces itching, swelling, and redness of the skin. The combination of betamethasone and clotrimazole topical is used to treat fungal skin infections such as athlete's foot, jock itch, and ringworm.Betamethasone and clotrimazole topical may also be used for other purposes not listed in this medication guide.he combination of betamethasone and clotrimazole topical is used to treat fungal skin infections such as athlete's foot, jock itch, and ringworm.