Minoxidil: mechanisms of action on hair growth

  title={Minoxidil: mechanisms of action on hair growth},
  author={A G Messenger and Jan Rundegren},
  journal={British Journal of Dermatology},
We have known for over 30 years that minoxidil stimulates hair growth, yet our understanding of its mechanism of action on the hair follicle is very limited. In animal studies, topical minoxidil shortens telogen, causing premature entry of resting hair follicles into anagen, and it probably has a similar action in humans. Minoxidil may also cause prolongation of anagen and increases hair follicle size. Orally administered minoxidil lowers blood pressure by relaxing vascular smooth muscle… 
Minoxidil use in dermatology, side effects and recent patents.
The mechanism of action of Minoxidil, a vasodilator medication known for its ability to slow or stop hair loss and promote hair regrowth, and use in dermatology and some patents related to alternative treatment of allergic reactions due to its use are described.
Preformulation Study of Minoxidil: A Drug for Androgenic Alopecia
The preformulation studies are prerequisite to ensure the development of therapeutically effective dosage form of Minoxidil and discussed the various characteristics of the drug i.e. pharmacodynamic and pharmacokinetic properties and others along with the mechanism of action.
The additive effects of minoxidil and retinol on human hair growth in vitro.
It is found that the significant hair shaft elongation demonstrated after minoxidil plus retinol treatment would depend on the dual kinetics associated with the activations of Erk- and Akt-dependent pathways and the prevention of apoptosis by increasing the Bcl-2/Bax ratio.
Thiosulfate promotes hair growth in mouse model
The hair growth-promoting effects of sodium thiosulfate (STS) in mice suggest that salts of thiosolfate may represent a novel and beneficial remedy for hair loss.
Human hair follicles contain two forms of ATP‐ sensitive potassium channels, only one of which is sensitive to minoxidil
It is indicated that human follicular dermal papillae contain KATP channels that can respond to minoxidil and that tolbu tamide may suppress hair growth clinically; novel drugs designed specifically for these channels could treat hair disorders.
Oral minoxidil in trichology: A review
The claim that high-quality studies are needed before advocating use of oral minoxidil in hair disorders remains undetermined, as when given in low dose, side effect profile of OM has been found comparable to that of TM.
The hair growth promoting effect of Asiasari radix extract and its molecular regulation.
HNG, A Humanin Analogue, Promotes Hair Growth by Inhibiting Anagen-to-Catagen Transition
Investigation of the promoting effect and action mechanisms of HNG on hair growth found that HNG stimulated the anagen phase longer with VEGF up-regulation, and it prevented apoptosis by activating Erk1/2, Akt, and Stat3 signaling.


Minoxidil sulfate is the active metabolite that stimulates hair follicles.
These studies show that sulfation is a critical step for hair-growth effects of minoxidil and that it is the sulfated metabolite that directly affects hair follicles.
Interaction of minoxidil with pigment in cells of the hair follicle: an example of binding without apparent biological effects.
This work illustrates how measurement of drugs in hair may be biased by pigmentation, and follows the uptake of radiolabeled drug in mouse vibrissae follicles both in vitro and in vivo.
Sulfation of minoxidil in keratinocytes and hair follicles.
  • T. Hamamoto, Y. Mori
  • Medicine
    Research communications in chemical pathology and pharmacology
  • 1989
Evidence is provided that sulfation of minoxidil occurs in the hair follicles and proliferative keratinocytes, which may be related to the hair growth stimulating effect of this drug.
Minoxidil-induced hair growth is mediated by adenosine in cultured dermal papilla cells: possible involvement of sulfonylurea receptor 2B as a target of minoxidil.
The results indicate that the effect of minoxidil is mediated by adenosine, which triggers intracellular signal transduction via bothAdenosine A1 and A2 receptors, and that the expression of sulfonylurea receptor 2B in dermal papilla cells might play a role in the production of adenosines.
Potassium channel conductance: a mechanism affecting hair growth both in vitro and in vivo.
The opening of intracellular potassium channels has been suggested as a mechanism regulating hair growth. Enhancing the flux of potassium ions is a mechanism shared by several structurally diverse
Biphasic effects of minoxidil on the proliferation and differentiation of normal human keratinocytes.
It was shown that Minoxidil had biphasic effects on the proliferation and differentiation of NHK: MinoxIDil stimulated NHK proliferation at micromolar doses, while antiproliferative, pro-differentiative and partially cytotoxic effects were observed with millimolar concentrations.
Action of topical minoxidil in the bald stump-tailed macaque.
The Effect of Topical Minoxidil on Hair Follicular Cycles of Rats
It is suggested that minoxidil specifically stimulates the secondary germ of the telogen follicles, resulting in rapid progression to anagen follicles.
Activation of cytoprotective prostaglandin synthase-1 by minoxidil as a possible explanation for its hair growth-stimulating effect.
It is demonstrated here that minoxidil is a potent activator of purified PGHS-1, as assayed by oxygen consumption and PGE2 production, and this activation was also evidenced by increased PGE1 production by BALB/c 3T3 fibroblasts and by human dermal papilla fibro Blasts in culture.