Minoxidil is a topical drug widely used to treat AGA (male pattern baldness) and other forms of alopecia. Although the mechanism by which minoxidil exerts its effects is not fully understood, several major mechanisms of action have been proposed. These are described in detail below.
Mechanism of action of minoxidil
- Hemodynamic promotion:
- Minoxidil was developed as a vasodilator. Initially used to treat high blood pressure, it was discovered to promote hair growth as a secondary effect.
- Dilating blood vessels increases blood flow to hair follicles and improves the supply of nutrients and oxygen to the follicles.
- It contributes to the activation of hair follicles and prolongation of the growth phase, thereby promoting hair growth.
- Direct action on hair follicles:
- Minoxidil acts directly on hair follicles, prolonging the growth phase (anagen phase) and accelerating the transition from telogen to growth phase.
- This increases the number of hairs in the growth phase and increases hair density.
- Increased cell growth factor:
- Minoxidil has been suggested to promote the production of cell growth factor in hair follicles.
- In particular, the production of vascular endothelial growth factor (VEGF) is increased, which helps in the angiogenesis (formation of new blood vessels) of hair follicles.
- This helps maintain follicle health and promotes hair growth.
- Anti-apoptotic effect:
- Minoxidil inhibits apoptosis (programmed cell death) of hair follicle cells.
- This extends the life of the hair follicle and maintains hair growth over a longer period of time.
Effects of minoxidil
- Increase in hair density:
- Clinical trials have shown that minoxidil increases hair density and makes hair grow thicker and longer.
- Hair loss is reduced and new hair growth is promoted.
- Effect after start of use:
- The effects of minoxidil are usually seen after 3-6 months of use.
- Continuous use is required to maintain effectiveness.
Precautions for use
- Side Effects:
- Topical application of minoxidil is generally safe, but mild side effects such as itching, dryness, and redness of the scalp may occur in some people.
- Rarely, systemic side effects such as low blood pressure and changes in heart rate have been reported.
- Continuous use:
- Minoxidil requires continuous use to maintain its effectiveness. Discontinued use may result in a gradual loss of effectiveness and a return to the original condition.
- Usage:
- Generally, a solution or form of minoxidil is applied directly to the scalp. The number of applications and the amount used vary by product, but twice daily application is usually recommended.
Summary
Minoxidil promotes hair growth through increased blood circulation, direct action on hair follicles, increased cell growth factor, and anti-apoptotic effects; in the treatment of AGA, it has been proven in clinical trials to increase hair density and decrease hair loss. Continuous use of the product, while observing the directions for use, will maximize its effectiveness. Appropriate use under the guidance of a medical specialist is recommended.
