Minoxidil 2% solution has been available since the late 1980s as a treatment for hair loss in both men and women. It is available over-the-counter (without prescription) as either a brand-name product (Rogaine ®) or in less expensive generic formulations. Minoxidil is applied topically-that is, applied directly to scalp skin where cessation of hair loss and stimulation of new hair growth is desired.
When first introduced, Rogaine received a great deal of media attention as the first hair restoration medication approved by the Food and Drug Administration. Some media stories implied it was a "miracle drug". Over time, Rogaine did not live up to "miracle drug" expectations and there was disappointment that results were often less than spectacular.
What can be said about minoxidil after more than a decade of use as a hair restoration medication? It can fairly be said that minoxidil is moderately effective and can be helpful for some people with hair loss. A 5% solution of minoxidil recently became available and clinical investigators have reported it to be considerably more effective than the 2% solution in halting hair loss and stimulating new hair growth in both men and women. At all formulations, women have been shown to have a better response than men to topical minoxidil.
Used as directed, 2% minoxidil has been shown to stimulate hair growth in about 30% of male patients, with a slightly higher rate in females. The response rate is improved with use of 5% solution.
Topical minoxidil in either 2% or 5% solution is most effective in persons with recent onset of hair loss due to androgenetic alopecia and relatively small areas of hair loss. Minoxidil is less effective when hair loss is long-standing or large in area. Thus, early use of minoxidil is indicated to prevent progression of small areas of male or female pattern hair loss. Physician hair restoration specialists sometimes use minoxidil to slow hair loss in young patients, delaying hair transplantation for several years in order to conserve the supply of hair that will be needed later for transplantation.
Minoxidil is often more effective in improving hair growth in central areas of the scalp than in frontal areas. It is often effectively used by physician hair restoration specialists to complement hair transplantation, contributing to an appearance of "fullness" in scalp hair.
If minoxidil proves effective in halting hair loss and/or stimulating new hair growth, its use becomes a lifetime commitment. If regular application of minoxidil is halted, all results of therapy will be rapidly lost over the next 3 to 6 months.
Side effects of topical minoxidil are few and generally minor skin irritation or itching. A potential complication of minoxidil use is the unwanted growth of facial hair if the minoxidil solution is accidentally spilled or applied to facial skin.
How Does Minoxidil Work?
Why does minoxidil halt hair loss and stimulate new hair growth? No one knows for sure, but there are some good assumptions.
The hair-restoration properties of minoxidil were an accidental discovery. Minoxidil was developed first as an anti-hypertensive-a drug designed to lower blood pressure by vasodilation (dilating blood vessels). But minoxidil also turned out to have an effect on the structure and cellular activity of hair follicles, and on the growth rate of hair. Is the vasodilating effect of minoxidil associated with its effect on hair follicles? No one can say for sure. It also is not known why the effects of minoxidil on hair follicles varies from person to person-no effect in some people, substantial effect in others. Since the cause of the hair follicle effects are not understood, they cannot be predicted and no one can say in advance who will benefit from minoxidil therapy and who will not.