Lots of people are under the impression that testosterone levels are decreased by taking finasteride, but does finasteride lower testosterone levels really? Well, l This is actually a myth, as finasteride does the opposite.
Finasteride works by decreasing levels of DHT, so less binds to the hair. However, since less testosterone is being converted to DHT, there is a higher level of testosterone. The key to protecting the hair is decreasing the levels of DHT.
Does finasteride lower testosterone levels?
Finasteride, AKA Propecia, does not lower testosterone but acts by decreasing the levels of circulating dihydrotestosterone (DHT), which decreases by about 70%. Free testosterone in circulation is actually increased, usually by about 10-20%. It does this by inhibiting the conversion of testosterone to dihydrotestosterone (DHT).
DHT is a culprit in hair loss, acting by binding to the hair follicle and thinning the hair. Eventually the hair falls out.
How does finasteride raise testosterone?
Finasteride’s mechanism of action is blocking the action of an enzyme called 5-alpha-reductase. This enzyme blocks the conversion of testosterone to dihydrotestosterone (DHT). So while the levels of DHT drop dramatically, there is most testosterone that is left unconverted which raises the blood levels of testosterone.
Finasteride Mechanism of Action
Finasteride’s mechanism of action is blocking the action of an enzyme called 5-alpha-reductase. This enzyme blocks the conversion of testosterone to dihydrotestosterone (DHT). So while the levels of DHT drop dramatically, there is most testosterone that is left unconverted which raises the blood levels of testosterone. There is another drug called Dutasteride, which is very similar to finasteride, but actually results in more decreased levels of DHT. Dutasteride inhibits 3 types of 5-alpha-reductase, which is why it results in a 99% decrease in levels of DHT rather than around 70% like you would expect with finasteride.
How much does finasteride increase testosterone?
When on finasteride, testosterone levels generally increase by about 10-20%. While it does vary, the vast majority of patients see an increase in that range. Usually this keeps people in the normal range for free testosterone, but it is always good to check and track the testosterone levels over time.
Finasteride effect on testosterone: Key takeaways
Finasteride is still the gold standard when it comes to preserving and thickening hair, but there are finasteride effects on testosterone. While it drops DHT by about 70%, which is essential for protecting and thickening hair, it also raises testosterone by about 10-20%. Sometimes there is an initial spike higher than 20% that drops back down while the body adjusts. It is always a good idea to track your hormone blood levels over time.
FAQs
Can I take finasteride and TRT together?
Yes, it is fine to be taking finasteride and testosterone together. While both are obviously raising testosterone, that doesn’t necessarily mean your testosterone levels will be too high. It is important to track your testosterone and DHT levels before you start, and periodically once you start treatment.
What other finasteride side effects should I be aware of?
There are finasteride hormone effects and it is possible to see slightly increased levels of estrogen after starting finasteride. The increased testosterone levels will result in some of the testosterone being aromatized to estradiol. Other side effects are erectile issues, decreased sex drive, and ejaculatory issues.
While not common, these side effects are known to occur for some people. Topical finasteride side effects are decreased very significantly, but all side effects will disappear after discontinuing the medication.
What happens if you take too much finasteride?
While nothing life threatening occurs with taking too much finasteride, there is evidence that taking too high a dose can put you at increased risk of having some sexual side effects. At higher doses, there is a higher incidence of side effects such as erectile dysfunction, decreased libido, etc.
What happens when I stop taking finasteride?
Once you stop taking it, it is metabolized and excreted over the course of a few weeks. At this point, your hair loss will return to how it was before. You lose the protection the finasteride provided, so your body will go back to the thinning it was doing before.
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