Inhibitors of 5a-reductase: Finasteride and Dutasteride

5a-reductase (5 alpha) is an enzyme responsible for the conversion of testosterone into its much more potent form DHT (dihydrotestosterone). The particularity and mode of actions of this group of medication is to inhibit the production of this enzyme, and hence blocking the conversion of T into DHT. DHT is considered to have masculinizing effects up to 10 times stronger than testosterone, and it is the main hormone responsible for hair loss (sometimes called “male pattern hair loss”). This is why the medications of this group (Finasteride and Dutasteride), are most commonly prescribed to cis-men seeking to reduce hair loss.

One problem is that the enzyme 5a-reductase is responsible for at least 9 other conversion reactions in the synthesis of steroid hormones. Consequently, inhibiting it does not only affect the conversion of testosterone to DHT.

An other problem is the medication won’t affect the levels of testosterone (the portion of T that would have been converted into DHT will remains as… testosterone), which will still run in the bloodstream, reach its receptors unhindered, and lead to masculinizing effects. This is why these medications will in no way be enough to block androgenic activity, and allow for feminization. It is only useful to reduce hair loss, and the best remains to consider another option to actually block the effects of testosterone (production or reception). Besides, low testosterone also means low DHT, since there is no testosterone to convert! This is how absurd the prescription of these medications is.

By opting for another blocker, you will find two benefits: Actually achieve better feminization, since with 5a inhibitors alone, your testosterone levels will remain unchanged. Avoid the negative side effects of the 5a inhibitors. These mostly come from the fact the 5a-reductase is also responsible for many other hormones synthesis, whose perturbation can cause anxiety, depression, suicidal ideation, neurological diseases and loss of libido.

The only reason to consider finasteride/dutasteride is if you managed to significantly reduce your testosterone by another way, but you still seem to be affected by hair loss, and you show abnormaly high levels of DHT on the blod tests. And considering the side effects, this decision should not be taken lightly.

Finasteride

Conceived for cis-men preoccupations: to reduce the levels of DHT (and hair loss associated) while keeping high levels of testosterone.

If you do not have abnormally high levels of DHT despite reducing your testosterone, taking finasteride is only taking unnecessary risks, without any benefits!

Finasteride is at the origin of the healthcare scandal called “Post-Finasteride Syndrome”. This “syndrome” is a set of effects such as anxiety, depression, suicidal ideation, neurological diseases and loss of libido. If this syndrome strikes a minority of finasteride users, they can be permanent, and persists after stopping the treatment.

Dutasteride

All what we said of finasteride is true of Dutasteride. The only difference is that dutasteride is able to prevent even more efficiently the conversion of testosterone into DHT.