S10 MINOXIDIL, THE STORY OF AN ADVERSE EFFECT THAT BECAME A NEW INDICATION

Whiting DA. Baylor Hair Research and Treatment Center, Dallas TX, USA.

Interest in the hair growing properties of minoxidil surfaced in 1979 with the advent of Loniten tablets. These minoxidil tablets for the reduction of blood pressure were approved by the American Food and Drug Administration and became available on prescription.  It soon became apparent that 80% of the patients taking Loniten tablets started growing excessive hair on the body.  The hair growth involved the face, shoulders, and trunk.  Later on it was noticed that patients with androgenetic alopecia were also growing new hair on their heads. This stimulated a great deal of interest and in due course a topical solution of minoxidil was compounded and tested.  It became apparent that hair could be grown with this compound and formal trials were initiated, firstly in males.  These showed that some visible hair growth could be expected in approximately one-third of those treated, with minor regrowth in another third of patients.  The regrowth did not appear in the remainder. However, some 80% of patients stated that the rate of hair loss had been decreased.  In due course, minoxidil became available in 1987 as topical Rogaine 2% and has been widely prescribed since. Studies in females were started later and somewhat similar results were seen.  The Rogaine 2% for females was approved by the FDA in 1989 and has been available since. In recent years the 2% minoxidil has been made available over-the-counter in America and in many other countries.  5% minoxidil has been available over-the-counter in men for the last few years. Topical minoxidil is now available in many countries around the world, either by prescription or as an over-the-counter product.  Its continuing use testifies to its value in preventing hair loss in many people and regrowing hair in a significant proportion of patients.