Minoxidil to Treat Androgenetic Alopecia in Men and Women: What is It & How does It Work?

Androgenetic alopecia (AGA) is hereditary, progressive hair loss which advances with age and affect mostly Caucasians. AGA is androgen-dependent for both genders but can also occur without involving androgen in women. This condition also can be inherited. Androgen-dependent processes are predominantly due to the binding of dihydrotestosterone (DHT) to the androgen receptor (AR). The predisposed scalp exhibits high levels of DHT, and increased expression of the AR. Conversion of testosterone to DHT within the dermal papilla plays a central role, while androgen-regulated factors deriving from dermal papilla cells are believed to influence growth of other components of the hair follicle. Minoxidil, an anti-hypertensive agent is being the mainstay of the AGA treatment for over 30 years now. Yet, the understanding of the exact mechanism of action of this drug is still unclear. There are few hypotheses on how does this drug works to promote hair growth. The hypotheses are based on the response of hair follicles and cellular response. The inconsistencies in the results shown for hair follicle response to minoxidil mediated by its sulphate form which acts as potassium channel opener, question the evidences. Cell cultures describe a variety of response to minoxidil and some of these could promote hair growth.