How Does Finasteride Work?

Finasteride is widely used as a treatment for AGA (male pattern baldness). The mechanism by which finasteride exerts its effect on AGA is as follows

Mechanism of action of finasteride

  1. Inhibition of 5-alpha-reductase:
  • Finasteride selectively inhibits the enzyme 5-alpha-reductase.
  • 5-alpha-reductase is an enzyme that converts testosterone into the more potent androgen dihydrotestosterone (DHT).
  • Finasteride has high inhibitory activity, especially against the type 2 isozyme of 5-alpha-reductase.
  1. DHT reduction:
  • The action of finasteride reduces the conversion of testosterone to DHT by inhibiting 5-alpha-reductase.
  • This reduces DHT levels in the blood and scalp.
  1. Reduced impact on hair follicles:
  • DHT has a strong inhibitory effect on hair follicles (hair roots), causing follicle miniaturization.
  • Miniaturized hair follicles will prevent hair growth and produce thin, short hair.
  • When DHT is reduced by finasteride, the inhibitory effect on hair follicles is reduced and follicular miniaturization is reduced.
  1. Normalization of the hair cycle:
  • The normalization of the hair cycle (hair growth cycle) occurs as the effects of DHT are reduced.
  • The growth phase is prolonged and the return of dormant hair follicles back to the growth phase is facilitated.
  • This increases hair density and decreases hair loss.

Effects of Finasteride

  • Increased hair growth: Clinical trials have shown that finasteride increases hair density and decreases hair loss.
  • Delay of progression: It has been shown to slow the progression of AGA, and with long-term use, the progression of hair loss can be reduced.

Precautions for use

  • SIDE EFFECTS: Side effects such as decreased libido, erectile dysfunction, and decreased semen volume have been reported in some men with the use of finasteride. These side effects are generally mild and often recover after discontinuation of the drug.
  • Prohibited use during pregnancy: Finasteride should not be touched or taken by women, especially if they are pregnant, as its use can affect the fetus.

Summary

Finasteride reduces DHT production by inhibiting 5-alpha-reductase, thereby reducing its inhibitory effect on hair follicles. This slows the progression of AGA and promotes hair growth. When using this product, it is important to use it appropriately under the guidance of a medical specialist, paying attention to side effects and contraindications.

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