Post Finasteride Syndrome - What's the truth?

Worldwide 10's of millions of men take Finasteride to treat and manage their hair loss, with more than 9 million prescriptions issued in the USA in 2017 alone. Originally Finasteride was developed as a medication to treat enlarged prostates in men, but as with any medication, more effects of the drug were observed during the clinical trials. 

And so Finasteride became a hair loss drug treatment with Merck & Co acquiring the patent under the brand name Propecia. 

How does Finasteride work?

Finasteride is a 5-alpha reductase inhibitor, which is the enzyme that causes the conversion of Testosterone to Dihydrotestosterone (DHT). This conversion takes place within various areas of the body. DHT plays a very important role during puberty in males. In essence it is a much potent by-product of testosterone and interacts with androgen receptors at a higher rate. The following are selective biological functions of testosterone and DHT in male puberty. 

DHT in our blood stream interacts with androgen receptor at the base of our hair follicles to cause androgenetic alopecia. The placement of these androgen receptors is determined the genes inherited from both parents. By preventing the conversion of testosterone to DHT, we can limit and prevent any further hair loss from being seen. In most cases some improvement will be seen when finasteride is taken as healthy hair growth resumes. 

Reported Side Effects

Merck undertook a large clinical trial using Finasteride as a hair loss treatment to prove its efficacy and to obtain an FDA-approval for the medication. Across 3 controlled clinical trials with a 12-month period, 945 men took 1mg of Finasteride daily with 934 taking a placebo medication. During the first year 36(3.8%) of the participants taking Finasteride reported one or more of the following side effects:

• Decreased Libido
• Erectile Dysfunction
• Ejaculation Disorder (Decreased volume)
• Discontinuation due to drug-related sexual adverse experiences

In total 1.4% of patients stopped taking the medication due to the side effects that they had seen. In the placebo group 1.6% of patients stopped their participation based on their perceived side effects.

All participants that stopped taking the Finasteride saw their side effects cease, will the majority that saw side effects and continued with the treatment also saw their side effects cease. By year 5 of the clinical trial, the incidence of side effects fell to below 0.3%.

Incidence of the following side effects were equal across the Finasteride and Placebo groups:

• Breast Tenderness and Enlargement
• Hypersensitivity Reactions
• Testicular Pain

The conclusion taken from the studies released for Finasteride is that there is no real danger to taking the medication, but how true were the results released?

Post Finasteride Syndrome

By 2016, 1370 product liability lawsuits had been brought against Merck in the USA and Canada in relation to permanent side effects from taking the medication.

There is a huge list of symptoms that this claimants are reporting as the permanent side effects that they have seen. These side effects cover sexual, physical and mental health. To date there have been 63 known suicides of Finasteride users. 

In 2019 an investigation by Reuters led them to believe that Merck know about the risk of permanent side effects, but hid them from the public. While none of this has been proved, Reuters are still campaigning for sealed evidence being used in the ongoing court cases to be made public. 

To date there is no conclusive proof that there is a risk of permanent side effects from taking the medications and there is a lot of misinformation on the internet around it. The only public information so far shows that there is a very small risk of sexual side effects, which are the most reported side effect as they can have the most profound mental effect on men. 

It is worth noting that a small study found that erectile dysfunction and depression is more common in men suffering from hair loss. This study only used men that were not treating their hair loss. Especially in young men, losing your hair can be extremely difficult to deal with and leave you low on self-confidence. Hair loss has long been a condition that men were expected to suffer with in silence and this makes them an extremely vulnerable demographic.

Keep an eye on how the legal cases in the USA unfold, and hopefully all the information Merck hold on Finasteride will make into the public eye.