What is Minoxidil?

Minoxidil was originally developed to treat high blood pressure. It is use for teating thinning hair was originally discovered when it was noted to cause increased hair growth as a side effect of this treatment. Topical Minoxidil is now the most widely recommended treatment for androgenetic alopecia. In the United States it is marketed as Rogaine and in New Zealand it is marketed as Regaine and recently a generic (and cheaper) version of topical minoxidil has become available under the brand name Headway.

How Minoxidil works?

How minoxidil works to grow hair is somewhat of a mystery. Since it was originally a blood-pressure pill and because it is a vasodilator it was thought that it worked by increasing the amount of blood to the hair follicles. However other vasodilators do not stimulate the same response so that it is now thought that minoxidil works by a different mechanism. Recent studies have shown that topical minoxidil does not cause an increase in skin blood flow which was originally though to be the mechanism by which minoxidil works. Studies carried out by L'Oreal recently suggest that minoxidil works by activating PGHS 1 (prostaglandin endoperoxide synthase-1) which helps promote hair growth.

How effective is topical minoxidil?

Topical minoxidil has been shown to be effective in both men and women. Clinical tests that were conducted by 27 US medical centers involving over 2,300 patients with male pattern baldness on the top of the head showed that after one year of use

48% of the men who had used minoxidil for one year rated their regrowth as moderate to dense.

36% of men who had used topical minoxidil for one year rated their regrowth as minimal

16% of men had no regrowth.

In tests carried out to evaluate the effectiveness of topical minoxidil on women almost two out of three women were evaluated by physicians to have regrown some hair.

How long do I need to use Minoxidil for?

Hair regrowth with topical minoxidil takes time. While some individuals see results faster then others studies show that at least 4 months of treatment is generally necessary before thee is any evidence of regrowth with topical minoxidil.

If treatment is successful the firt thing you will notice is less shedding within 90 days of beginning treatment. This is because minoxidil may prolong the growth phase of the hair cycle, thus increasing the number of follicles in the growth phase at the same time.

New growth may be soft, downey and barely visible at first. This can be an encouraging sign because it shows that minoxidil is actually stimulating regrowth. If you continue to respond with further treatment the soft downey gowth may change into hair of the same colour and thickness as the other hairs on your scalp.

Because Minoxidil is a treatment, not a cure further progress is only possible by using minoxidil continuously over the long term to oppose the normal genetic process in the affected follicles. Lapses in theapy or discontinuationin therapy can cause follicles artificially kept in the growth phase to enter the resting phase. If you stop using minoxidil you will probably loose the regrown hair within a few months.

Studies involving Minoxidil

STUDY: Dose-response study of topical minoxidil in male pattern baldness.

STUDY: Minoxidil sulfate is the active metabolite that stimulates hair follicles.

STUDY: Relationship between contact time of applied dose and percutaneous absorption of minoxidil from a topical solution.

STUDY: Effects of hypertrichotic agents on follicular and nonfollicular cells in vitro.

STUDY: Topical minoxidil for hair regrowth.

STUDY: Potassium channel conductance: a mechanism affecting hair growth both in vitro and in vivo.

STUDY: Enhanced in vitro hair growth at the air-liquid interface: minoxidil preserves the root sheath in cultured whisker follicles.

STUDY: Hair growth effects of oral administration of finasteride, a steroid 5 alpha-reductase inhibitor, alone and in combination with topical minoxidil in the balding stumptail macaque.