A method of treating diseases caused by sebaceous gland disorders, in humans and animals, which comprises administering to said humans and animals a composition comprising a sebaceous gland secretion inhibiting amount of an active compound comprising an acyl coA cholesterol acyl transferase (ACAT) inhibitor or prodrug therefor. A composition for use in treating diseases caused by sebaceous gland disorders such as acne in humans and animals which comprises a sebaceous gland secretion inhibiting amount of an acyl coA cholesterol acyl tanferase (ACAT) inhibitor or prodrug therefor and, optionally, a pharmaceutically acceptable carrier.