Relationship Between Contact Time of Applied Dose and Percutaneous Absorption of Minoxidil From a Topical Solution

This study from 1990 investigated the relationship between the contact time of applied dose and percutaneous absorption of minoxidil from a topical solution. The study involved applying doses of minoxidil to bald scalps of subjects and collecting urine samples to determine the extent of percutaneous absorption. The results showed that the extent of percutaneous absorption increased in a disproportionate manner with an increase in topical solution exposure time on the scalp. The study concluded that minoxidil metabolism does not appear to be influenced by the extent of systemically absorbed drug. Further research is needed to understand the factors controlling percutaneous minoxidil absorption.