Transdermal and trans-membrane delivery of drugs

A method for increasing the rate of passage of a drug across animal or human skin, mucous membranes, or the blood brain barrier which comprises applying to the skin, mucous membrane or blood brain barrier a composition comprising an effective amount of the drug, a pharmaceutical carrier, and from about 0.1 to about 50% by weight of a compound (with or without dissolving in a solvent) effecting such increase in rate, said compound having the structure:

• ##STR6## wherein X and Y are oxygen, sulfur or an imino group of the structure ##STR7## or .dbd.N--R, with the proviso that when Y is an imino group, X is an imino group, and when Y is sulfur, X is sulfur or an imino group, A is a group having the structure ##STR8## wherein X and Y are as defined above, m and n are integers having a value from 1 to 20 and the sum of m+n is not greater than 25, p is an integer having a value of 0 or 1, q is an integer having a value of 0 or 1, r is an integer having a value of 0 or 1, and each of R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 is independently hydrogen or an alkyl group having from 1 to 6 carbon atoms which may be straight chained or branched, provided that only one of R.sub.1 to R.sub.6 can be alkyl group, with the proviso that when p, q and r are 0 and Y is oxygen, then m+n is at least 11, and with the further proviso that when X is an imino group, q is equal to 1, Y is oxygen, and p and r are 0, then m+n is at least 11.