Skin penetration enhancement using free base and acid addition salt combinations of active agents

摘要

The invention is directed to compositions for topical application made up of active pharmaceutical permeants capable of existing in both free base and acid addition salt form. The permeants are present as a combination of both free base and acid addition salt forms. These combined forms provide skin penetration rates which are greater than the penetration rate of either the free base or acid addition salt forms utilized separately. The combined free base-acid addition salt permeants are formulated in a carrier vehicle which preferably also possesses skin penetration enhancement activity.