1. Introduction

Finasteride is a drug used for the treatment of:

  • Benign Prostatic Hypertrophy;
  • Prostate cancer;
  • Androgenetic alopecia (common baldness)

The drug is produced by the pharmaceutical company Merck. It is present on the american market since 1992 for the cure of the prostatic hypertrophy and since 1997 for the treatment of common baldness. It is available on the italian market since 1997 for the prostatic hypertrophy and since 1999 for androgenetic alopecia. It is a very efficient drug, unfortunatelly sometimes used as doping in the sports world in order to hide some of the sides effects of some nabolic steroid.

  1. The discovery

It all began in 1974 when Julianne Imperato-McGinley, a New York researcher for the Cornell Medical College, during a debate in a conference about birth defects, presented her research. Her studies had focused on a group of hermaphrodites children who lived in the Caribbean. The children have been grown as females from their families, since their traits were unclear and they presented very small masculine genital organs. During puberty although, the masculine organs developed and their traits changed a lot.

Some studies proved that the genetic mutation of the children was due to a shortage of 5-alfa reduttasi enzyme and, consequently, of the diidrotestosterone (DHT) hormone. That is why the reproductive system had developed uncorrectly. Moreover, it was observed that, after the development, the prostate of the guys was very small.

Focusing on this detail, the leader of the research at the pharmaceutical company Merck developed his idea. He understood that it was possible to synthesize an inhibitor for 5-alfa reduttasi enzyme in order to reduce the dimensions of the prostate for the patients affected by benign prostatic hypertrophy.

  1. What is Finasteride?

Finasteride is a compund of sinthetic 4-azasteroide and it is the progenitor of all the inhibitors of the enzyme responsable for the benign prostatic hypertrophy. It is a white, crystalline substance, soluble in chloroform and insoluble in water.

  1. Finasteride and hair loss

Finasteride is one of the most prescribed drugs for the treatment of baldness. Androgenetic alopecia, or common baldness, is caused by the action of some androgens hormones on the hair follicles of the scalp.

In particular, the diidrotestosterone (DHT), an hormone that develops because of the action of a specific enzyme (5-alfa-riduttasi type 2) on the testosterone, is the responsabile for the miniaturization of the hair follicles. Hair gets thinner, loses its characteristic color and does not regrow after the fall.

Finasteride is able to oppose the hair thinning by taking action on the sinthesis of the DHT in the tissue, by selectively inhibiting the 5-alfa reduttasi type 2.

Finasteride is prescribed with the aim to reduce the DHT level in order to prevent the miniaturization and, in some cases, to favor a new regrowth.

One of the positive aspects of Finasteride is that it inhibits tha action of the enzyme without stopping the physiological action of the testosterone, a foundamental hormone especially in men.

  1. Dosage and formality of assumption

Finasteride has to be taken orally, if we want it to work properly against hair loss. That is why Finasteride is available on the market as a pill to ingest by mouth.

We remind that, on the market, Finasteride appears with the registered mark Proscar, with a concentration of 5 mg, and Propecia, 1 mg. The daily suggested dosage to fight baldness is 1mg per day.

The maximum concentration is reached in around 2 hours, while the absoption lasts around 8 hours.

  1. Does Finasteride work?

Several studies have shown the effectiveness of Finasteride in curing baldness. Around one year after the assumption, around the 50% of the male patients between 18 and 41 years old sees a decrease in the hair loss, while the other half also notices a regrowth. In less that 1% of the cases, Finasteride has been ineffective.

One of the reasons that makes Finasteride so effective is the formality of assumption. Another suggested drug for baldness is Minoxidil, but it cannot be assumed orally.

After orally taking the pill, Finasteride is immediately absorbed by the intestine. After 24 hours it is already possible to record a 65% reduction of the DHT concentration. However, in order to see all the benefits of the drug, it is necessary to keep on assuming it for at least 3 months. The experts suggest, in general, a therapy of at least 12 months, in order to evaluate properly all the achieved effects. Moreover, it is opportune to underline that the benefits of Finasteride last only until the drug is taken and disappear when the therapy is interrupted.

Another matter is the one about women. On them, Finasteride seems to be less effective, especially during the menopause, when the hair loss is due to the estrogens. Women in childbearing age cannot take the drug because of the risk of pseudoermafroditism of the fetus due to the too aggresive action of the hormones.

  1. Side effects of Finasteride

Finasteride is usually well tolerated by the organism. However, as we said before, it is necessary that the cure lasts long, at least 3 months, in order to see some results against hair loss. In many cases it is necessary to assume the drug for more than a year. That kind of assumption scares the patients, also given the information that can be found on the internet about the sides effects on the sexual sphere.  Side effects usually do not show and, when they do, are small. Around 3%-4% of the patients complain about some of the following sides:

  • Libido decreased: the libido is the phycological ability to respond to the sexual and physical stimulus. It is a pulsion, a desire that guides the sexual act and that makes it pleasant. Without it the sexual act is only mechanical. Libido does not have to be confused with the sexual potency, the strictly physical ability to have sex. Of course it is important to underline how, very often, pshycological dimension and physical act go hand in hand.
  • D.:inability to have an erection or to keep it, even if there is sexual desire at a pshycological level.
  • Reduction on the volume of the semen: a decrease in the quantity of the semen produced;
  • Unilateral gynaemastia: the enlargement of one of the masculine breasts.
  • Alteration of the spermatogenesis(only if correlated to varicocele or obesity): a process that brings to the maturation of the masculine germinal cells inside the testicles for an hormonal action.
  • Listlessness: indolence in fulfilling everyday necessities.

Some articles talk about a correlation between Finasteride and prostate cancer, however there is no certain proof of this connection. The sides of Finasteride are transitional and end immediately after the interruption of the therapy.

  1. Post-Finasteride syndrome. Does it really exsist?

Around 5 years ago, the american blog “Propecia Help” has used for the first time a term that is nowadays pretty common between Finasteride users: post-Finasteride syndrome.

This term indicates one of the biggest fear of who is about to star a Finasteride therapy in order to fight hair loss and androgenetic alopecia.

With this term we refer to a neurological and psychiatric condition that shows as consequence of the reduction of the libido due to the assumption of Finasteride. Actually, as we said, there are a few studies that show that a little percentage of Finasteride users complain some sides affects on the sexual phere. Libido decreased, E. D. and reduction of the volume of the semen have affected the 3,8% of the users after a year. After 5 years the percentage reduces to 3,5%. However, it has been proved that when the assumption is interrupted, the sides disappear.

For sure, this kind of sides effects have a big impact on the pshycological dimension of the person. A decrease in self-esteem, fear of a permanet damage, discomfort, anxiety are just some of the effects. For a young man, this could be an hard trauma to overcome, and it could last also after the end of the therapy.

However, although the great interest by the pubblic in this topic, there are no studies that prove the existence of the post-Finasteride syndrome.

  1. Contraindications

  • The drug is effective only on males;
  • Pregnant women have to avoid touching the pills, since the active substance can be absorbed though the skin. Finasteride can cause a malformation of the external genitals of the fetus.
  • Since Finasteride is metabolised by the liver, before starting the therapy, you have to be sure not to suffer from hepatic impairment.
  • Studies about fertility in men in the long term have not been carried out.
  1. Finasteride for women

Finasteride is approved only for men. However, there are many off-label uses.

In fact, Finasteride is effective on women for the cure of androgenetic alopecia and hirsutism (abnormal hair growth in areas where hair usually does not grow). Although, the researchers recommend to strictly follow the claims of the package leaflet.  Years of research are necessary in order to ensure that Finasteride can be taken also by women without risks.