Oral finasteride was first approved for the treatment of androgenetic alopecia (male pattern hair loss) in 1997. The medication works by lowering levels of an androgen (male sex steroid hormone) called dihydrotestosterone (DHT), a primary cause of thinning hair in men. Clinical studies support the drug’s efficacy and tolerability, but there are side effects of finasteride that you should be aware of.
Finasteride side effects: What are they?
The most commonly reported side effects of oral finasteride include:
- Erectile dysfunction
- Decreased sex drive (libido)
- Gynecomastia (breast swelling)
- Breast pain
Less common side effects of oral finasteride include:
- Decreased ejaculatory volume
- Lowered sperm count
- Suicidal ideation
- High-grade prostate cancers
In general, finasteride is a well-tolerated medication. Many men are able to take the drug without experiencing any unwanted effects. However, some men may be at a higher risk of developing side effects due to factors such as pre-existing medical conditions or genetic differences that can affect how the body responds to the drug or changes in androgen levels.
Finasteride side effects: How common are they?
Safety data on finasteride has shown that sexual side effects (e.g. erectile dysfunction, decreased sex drive and ejaculatory disorders) are the most common type of adverse effect. A review of several studies on the use of finasteride to treat male pattern hair loss found the incidence of sexual side effects to be 2.1-3.8% compared to placebo (Mysore & Shashikumar, 2016).
Finasteride sexual side effects
Within the category of sexual side effects, one review found that erectile dysfunction was reported by 3.4-15.8% of study participants receiving finasteride treatment. This was in contrast to 1.7-6.3% of participants in the placebo (control) group. The incidence of decreased sex drive was 2.36-10.0% compared to 1.2-6.3% (placebo), while ejaculatory changes were reported by 0.9-5.7% and 0.5-1.7% (placebo) of men (Hirshburg et al., 2016).
Is depression a side effect of taking finasteride?
Possibly, but a direct link has not been established. When oral finasteride was first approved for the treatment of hair loss in men, depression and mood changes were not listed as possible adverse effects. However, post-market and subsequent clinical trial data showed that enough men were reporting these effects to revise the original safety labelling.
It’s difficult to know the exact frequency of psychiatric symptoms. Sample sizes for studies are typically small and there are confounding factors within study populations such as the inclusion of patients with a history of mental illness or sexual dysfunction. It is also unclear whether these side effects are long-lasting or permanent.
There are a few possible explanations for why finasteride may cause mood changes in certain individuals. One theory is that depression is indirectly connected to low androgen levels. The blocking action of the 5-alpha reductase enzyme lowers DHT concentrations, but also reduces the production of other steroids such as neuroactive steroids (Romer & Gass, 2010). These steroids have mood stabilizing properties.
What causes side effects of finasteride?
Side effects of finasteride are thought to be due to systemic exposure to the medication when the drug is taken orally. When it is absorbed into the body through the digestive tract, finasteride lowers blood levels of the hormone dihydrotestosterone (DHT), which may have negative effects on androgen-sensitive tissues located throughout the body. These side effects may be reduced if finasteride is delivered via a non-oral route (e.g. topically).
Finasteride side effects: How long do they last?
In general, side effects associated with oral finasteride are temporary. They improve over time with continued use of the medication (Hirshburg et al., 2016). In recent years, there have been reports of side effects persisting even after stopping treatment, a phenomenon known as post-finasteride syndrome (PFS). Studies conducted so far on PFS agree that side effects need to be properly managed, since these can have a serious impact on quality of life.
It is important to note that there is currently a lack of conclusive evidence to support that these long-term effects are directly caused by the medication. In the case of sexual side effects, it is important to understand that there are both psychological and physiological components to the human sexual response and performance. In at least one study, counselling on the possible risks of treatment resulted in a higher incidence of reported side effects (Mondaini et al., 2007).
What should I do if I experience side effects while taking finasteride?
Side effects while taking finasteride can be concerning. But there are a few things you can do to ensure that you’re prioritizing your health and safety throughout treatment:
Talk to a doctor.
If you think you might be experiencing side effects while taking finasteride, you must notify a healthcare professional. They may suggest changing the dosage of finasteride, or trying a different treatment to avoid side effects.
Lower the dose.
Your doctor may recommend trying a lower dose of finasteride. Less medication in the bloodstream may help reduce the risk of developing side effects. You should never alter dosing yourself, but can discuss this with a doctor.
Consider your options.
Instead of the oral drug, you could consider using topical finasteride. Topical forms of finasteride are referred to as compounded medications and must be prepared by a specialized compounding pharmacy based on a doctor’s prescription. The compounding process combines FDA-approved finasteride with a carrier or base such as SiloxysSystem™ Gel. This allows finasteride to be applied directly to the skin.
In contrast to oral finasteride which must pass through the digestive system before reaching target hair follicles at the scalp, Topical Finasteride, with SiloxysSystem™ Gel delivers the medication to the hair follicles directly. In this way, the gel was designed to minimize absorption of finasteride into the bloodstream and reduce the risk of developing side effects.
In comparisons of topical finasteride vs oral finasteride, topical formulations have been associated with a decreased risk of sexual side effects (Lee et al., 2018). A doctor will need to determine if topical finasteride is an option for treating your specific case of hair loss.
Finasteride side effects: Takeaway
Every medication carries a risk of side effects and finasteride is no exception. This is why it’s important to maintain regular communication with your doctor and alert them to any adverse effects you might be experiencing.
Still concerned about side effects?
Start a free consultation with an board-certified dermatologist today through XYON to see if Topical Finasteride, with SiloxysSystem™ Gel might be a reasonable solution to your thinning hair.