Does Finasteride Cause Erectile Dysfunction?

Finasteride is one of the most promising medicines against male pattern baldness and benign prostatic hyperplasia (BPH). It achieves this by reducing the levels of dihydrotestosterone (DHT) that cause hair loss and enlargement of the prostate. 

Although practical, sexual side effects, more specifically, erectile dysfunction (ED), have been a factor that many males consider when it comes to whether the use is worth the risks.

How common is ED with finasteride? Is it short-term or long-term? Are there other alternatives? Let us take a look at what the research says.

What Is Finasteride and How Does It Work?

Finasteride, also known by its brand names Propecia or Proscar, is the gold standard medication used to treat male pattern baldness, as well as a first-line treatment for benign prostatic hyperplasia (BPH) or an enlarged prostate. It works by reducing the hormone dihydrotestosterone (DHT), a derivative of testosterone.

Finasteride inhibits an enzyme known as 5-alpha reductase, which converts testosterone into dihydrotestosterone (DHT). Finasteride can reduce DHT levels in the body by up to 70%, which helps slow hair follicle damage and decrease the size of the prostate. While this is beneficial, in individuals sensitive to changes in this hormone, a reduction in DHT can cause rare and unwanted side effects.

Approved indications: BPH and androgenetic alopecia

The FDA has approved finasteride to treat two primary conditions:

Benign Prostatic Hyperplasia (BPH): Increases the flow of urine and lessens the chances of acute urinary retention

Androgenetic Alopecia (Male Pattern Baldness): Assists in retaining current and preventing progressive hair loss, primarily on the top and mid-scalp.

Notably, the effects do not appear immediately; it takes months before results are seen, and when finasteride is discontinued, benefits are lost within 6 to 12 months.

Dosage Forms: Oral vs. Topical Spray

Oral Finasteride reduces DHT systematically; however, it offers excellent outcomes with hair loss and benign prostatic hyperplasia with somewhat greater sexual side effects.

Topical sprays or foams directly target scalp DHT, resulting in reduced systemic absorption because of their foamed or sprayed nature.

Does Finasteride Cause Erectile Dysfunction?

Subsequently, among the most widespread concerns regarding the use of finasteride in either an attempt to prevent hair loss or to treat hair loss is the possibility of it leading to erectile dysfunction. Although the drug works equally on male pattern baldness as well as benign prostatic hyperplasia, it is the sexual side effects that appear to be of concern to most men.

Clinical incidence rates (2–4%)

Studies have discovered that sexual side effects (problems with erectile dysfunction, low sex drive or ejaculatory dysfunction) take place in approximately 2 to 4 per cent of men receiving finasteride.

The majority of clinical trials, as published in the Journal of Sexual Medicine and cited by the American Urological Association, indicate that the problems are typically mild and can be resolved by discontinuing the medication. 

What are possible risk factors? age, dose & comorbidities

Not every man has an equal risk of developing the side effects of finasteride. The difference may occur due to age, dosage, or health conditions. 

Additional risk factors are a pre-existing erectile dysfunction, cardiovascular disease, diabetes, obesity, or uncontrolled stress levels, each of which can cause ED on its own.

Does Topical or Spray Finasteride Carry the Same Risk?

Because of the worry that men will get erectile dysfunction using oral finasteride, ideas about alternatives, like topical sprays and solutions of finasteride, have been of interest. But are the topical forms equally liable to sexual side effects?

Evidence on reduced sexual side effects

In early clinical trials and observational studies, the sexual side effects are reduced among patients who use topical doses of finasteride compared to those using oral finasteride.

Scalp DHT decreased by over 50 per cent in some patients with little change in serum DHT. Consequently, topical routes can be used in men who want to treat hair loss without the same systemic effects. 

Application frequency & concentrations

Topical finasteride is usually administered once or twice daily. Other combination treatments prescribe even combinations of finasteride and Minoxidil to boost regrowth. 

Because the drug is applied topically to the scalp, there is a perceived reduced risk of metabolic hormonal consequences, like a loss of libido or erectile dysfunction, compared to the traditional 1 mg dose of the drug taken orally.

Comparatively, Dutasteride, a slightly more potent 5-alpha reductase inhibitor sometimes used in cases of extreme hair loss, has a longer half-life and a greater effect on DHT levels, making it more likely to influence hormones.

How Does Combining Minoxidil and Finasteride Affect Sexual Side Effects?

Finasteride may be combined with Minoxidil, as many men seek to actively prevent hair loss actively, especially after undergoing a hair transplant. But is the risk of sexual side effects increased with this two-fold approach?

Finasteride is used to combat the hormonal factor in hair loss, lowering the amount of DHT in the scalp. Minoxidil helps to increase blood flow to the scalp and extend the hair growth cycle. 

When used together, they produce superior outcomes than when used individually. Minoxidil does not act on hormones, so it is unlikely that the addition would escalate sexual side effects any more than those that could otherwise happen in the case of Finasteride.

Are Erectile Dysfunction Effects Permanent or Temporary?

The primary concern regarding the use of Finasteride in preventing hair loss is whether the sexual effects of this medicine are long-term or not, e.g. an inability to have erections or a loss of sex drive. 

Although the vast majority of men report tolerating the medication well, a minority develop alterations in sexual functioning, which can be a worrying aspect regarding its long-term implications.

What happens after using Finasteride (Post-finasteride syndrome controversy)

Some men complain of continuing sexual symptoms, which are sometimes referred to as Post-Finasteride Syndrome (PFS), even after quitting the medication. The symptoms can be persistent erectile dysfunction, decreased sex drive, exhaustion, and mental problems. 

Nonetheless, this condition is controversial, with inconsistent studies, and the underlying mechanism remains unclear. 

Some think that psychological issues or unrelated medical problems may cause it. On the other hand, some people point out that long-term hormonal alterations might cause these symptoms.

How to Reverse Post-Finasteride Syndrome/issues

In case of sexual side effects, physicians can recommend a drug holiday, i.e. temporarily stopping Finasteride to determine whether the symptoms subside. 

Erectile dysfunction, in most instances, recovers following withdrawal of the drug. 

For patients who wish to undergo further hair loss treatment, it is recommended to replace the topical application of Finasteride with a smaller dose or an alternative drug, such as Minoxidil, to maintain results with less impact on the system.

What Alternatives Are Available If You Experience ED?

In case you encounter erectile dysfunction during your course of taking Finasteride, you do not necessarily have to drop out of hair treatment altogether.

 The number of non-hormonal and topical methods to promote or maintain hair growth is quite extensive, and these methods do not significantly affect hormone levels.

Switching to topical DHT blockers (e.g., azelaic acid)

The first alternative is to switch to topical DHT blockers that act locally on the scalp and are not systemically absorbed. Products such as azelaic acid, caffeine-based serums, or even topical Finasteride aim to reduce DHT levels in the scalp without affecting hormones in the body.

Non-hormonal options: PRP, microneedling & laser

In case you want to use entirely non-hormonal treatments, these are some of the possible solutions:

• PRP therapy utilises the blood plasma, which carries growth factors in your blood, to rejuvenate inactive hair follicles and enhance scalp health.
• Microneedling works by creating minor, controlled injuries to the scalp that improve blood flow, stimulate new hair growth, and increase the absorption of topical treatments, such as topical Minoxidil.
• Low-level laser therapy (LLLT) uses light energy to enhance cell activity in the hair follicles and retard the thinning process.

These treatments do not have an impact on your hormone levels, and thus, they are perfect for men who suffer from ED or other side effects of oral DHT blockers.

Conclusion

Finasteride is still among the best options to serve both male pattern baldness plus BPH, and the side effect is only experienced by a limited number of its users.

Even if you experience Erectile Dysfunction, it is mild and reversible in the majority of cases, provided it is detected early.

For men concerned about the systemic effects, topical Finasteride or the introduction of Minoxidil can be used to preserve hair growth with less risk. Such non-hormonal treatments as PRP, microneedling, or laser also aid hair restoration and do not affect sex life. With the right medical advice, regular check-ups, and individualised medication, Finasteride can be taken safely without incurring many side effects.

FAQs

1. Does finasteride always cause erectile dysfunction?

No. Erectile dysfunction is not experienced in most men. Medical reports indicate that it only affects 2 – 4 in 100 users, and it is both mild and reversible.

2. Can finasteride spray cause ED?

There is also low systemic absorption with the Topical Finasteride spray, so the chances of ED are minimal as opposed to taking the oral tablet.

3. Does topical finasteride reduce ED risk?

Yes. Topical Finasteride seems to reduce the possibility of sexual side effects by acting predominantly on the scalp and not causing changes in the rest of the body in the form of hormonal changes.

4. Can combining minoxidil and finasteride worsen ED?

No. Minoxidil is not hormonal and does not raise the risk of ED. Its combination with Finasteride helps to enhance hair growth, without exacerbating sexual side effects.

5. How soon does ED appear after starting finasteride?

In case it happens, ED usually takes place during the early weeks or months of the treatment.

6. Is ED from finasteride reversible?

In most instances, yes. The erectile ability is typically restored in the days or weeks after stopping the drug.

7. Are there lower-dose finasteride options?

Yes. To minimise side effects while continuing the benefits, some men take half doses, alternate-day doses, or switch to topical Finasteride.

8. What if I experience persistent ED?

You must see a physician immediately. Some of the options available are discontinuing Finasteride, topical treatments, ED (erectile dysfunction) treatment, and non-hormonal hair loss options (PRP or laser).

References

• American Urological Association (2020) Guidelines on medication-induced erectile dysfunction. Available at: https://www.auanet.org (Accessed: 16 July 2025).
• Healthline (2024). Finasteride for Hair Loss: Benefits, Side Effects, and FAQs Available at: https://www.healthline.com (Accessed: 16 July 2025).
• International Journal of Dermatology (2023) Topical dihydrotestosterone blockers and sexual side effect profiles. International Journal of Dermatology, 62(4), pp. 451–459.
• Journal of Sexual Medicine (2022) Incidence and reversibility of sexual dysfunction in men taking finasteride: A systematic review. Journal of Sexual Medicine, 19(7), pp. 1054–1063.
• PubMed (2023) Post-finasteride syndrome: clinical evidence and ongoing debates. Available at: https://pubmed.ncbi.nlm.nih.gov (Accessed: 16 July 2025).
• International Society of Hair Restoration Surgery (ISHRS) (2024). Combination therapies for hair loss: finasteride, minoxidil, and beyond. Available at: https://ishrs.org (Accessed July 16, 2025).