What is it used for? This cream and ointment are used in short courses to treat inflammatory skin conditions such as those listed below, when milder corticosteroids have not been effective and when the condition is either already infected or likely to become infected. How does it work? When betamethasone is applied to the skin it works by acting inside the cells to decrease the release of these inflammatory substances. This reduces swelling, redness and itch. Betamethasone is a potent corticosteroid. Neomycin is an antibiotic of the aminoglycoside type and is used to treat infections with bacteria. It works by affecting the bacteria's production of certain proteins that are necessary for their survival. It causes the bacteria to produce abnormal and faulty proteins. This ultimately kills the bacteria. Neomycin is included in this preparation to treat the bacteria that sometimes infect inflammatory skin diseases.