Compounds of formula (I) (in which R<；SUP>；1<；/SUP>；； R<；SUP>；2<；/SUP>；, R<；SUP>；3 <；/SUP>；and R<；SUP>；4 <；/SUP>；are the same as or different from each other and each represents an oxo group, a hydroxy group, a mercapto group, a hydrogen atom, a halogen atom, an alkoxy group or an aryloxy group； and the dotted line indicates that there may be a single or double bond between one of the respective pairs of carbon atoms) and esters thereof can be administered by transdermal administration. They are particularly effective when applied as a patch, preferably with an adhesive comprising a copolymer of from 40 to 60% by weight of methoxyethyl acrylate, from 30 to 40% by weight of lauryl acrylate or lauryl methacrylate and from 10 to 25% by weight of a polar monomer.
