Does Finasteride Cause Depression? - Putting it in Perspective

Post-Finasteride Syndrome (PFS)

Concerns regarding finasteride and its potential link to depression are not new. In 2012, a pivotal study by Dr. Michael Irwig (Irwig, 2012) became the first clinical investigation to document significant depressive symptoms and suicidal thoughts specifically among former finasteride users who developed persistent sexual side effects. The publication coincided with the founding of the Post-Finasteride Syndrome

Foundation and increased media scrutiny—factors researchers believe may have contributed to a rise in adverse-event reporting after 2012. “Post-Finasteride Syndrome” (PFS) is defined as a cluster of adverse effects that develop during or after finasteride exposure and persist even once the drug is discontinued. It is

not limited to depression; rather, it represents a multisystem condition encompassing sexual (e.g., erectile dysfunction, libido loss), physical, and neurological/psychological symptoms, with depression occurring in roughly 50% of those identified as having PFS.

Sounding the Alarm

Possibly because of the rise in online prescribing of finasteride through services like Hims and Keeps, and/or because digital media accelerates dissemination of medical concerns, some observers are "sounding the alarm" again about an association between finasteride and depression. A recent paper in the Journal of Clinical Psychiatry, by public health researcher Professor Mayer Brezis concluded that “current evidence shows that finasteride use can cause depression and suicidality” (Brezis, 2025). The author notes that from 2017 to 2023, multiple independent analyses—eight studies in total—consistently found increased risks of depression, anxiety, or suicidal behaviors in finasteride users. All eight studies, including analyses of pharmacovigilance databases and healthcare records, reported an association between finasteride and serious mood or anxiety outcomes. The review emphasizes that the convergence of these findings—8 out of 8 studies showing risk—is unlikely due to chance and suggests a strong causal link.

The article raises valid concerns about transparency in reporting medication side effects and the timeliness with which such information is communicated to the public. However, its conclusions are premature and overstated, and they may not be generalizable to patients using these medications for hair loss. The paper also appears selectively to include studies that reinforce a predetermined viewpoint rather than offering an unbiased, comprehensive review of the literature.

How might finasteride lead to depression?

The link between finasteride and mood disorders has biologic plausibility. Finasteride reduces neurosteroid levels such as allopregnanolone, which normally exert antidepressant effects, providing a mechanistic explanation for its potential to induce depression or anxiety. The theorized link between 5-alpha reductase inhibitors (5ARIs) and mood disorders centers on the blockade of neuroactive steroid synthesis (Brezis, 2025; Welk et al., 2017). The enzyme 5-alpha reductase converts progesterone and testosterone into

neurosteroids like allopregnanolone, which modulate GABA-A receptors and produce antidepressant and anxiolytic effects (Garcia-Argibay et al., 2022; Lyakhovitsky et al., 2024). By inhibiting this enzyme, both finasteride and dutasteride reduce levels of these theoretically neuroprotective steroids, a change hypothesized to precipitate depression and anxiety (Garcia-Argibay et al., 2022).

Pharmacologically, dutasteride is the more potent inhibitor—blocking both type I and type II isoenzymes and reducing DHT by over 90%—whereas finasteride selectively inhibits type II, reducing DHT by roughly 70% (Garcia-Argibay et al., 2022; Nguyen et al., 2021). Because reduced expression of type I 5-alpha reductase in the prefrontal cortex has been associated with depression, dutasteride might theoretically pose a greater psychiatric risk, despite receiving less attention with respect to mood-related adverse effects (Welk, 2017). However, clinical data suggest we may not need to be equally concerned about both medications regarding severe outcomes—potentially due to pharmacokinetics. While some studies found that both drugs carried a similarly increased risk of depression (Garcia-Argibay et al., 2022; Welk et al., 2017)—or no increased risk for either (Neubauer et al., 2025)—others identified significant differences in suicide risk. One major study reported that finasteride is known to cross the blood-brain barrier, whereas it remains unclear to what extent dutasteride does (Laanani et al., 2023). This difference in CNS penetration may explain why finasteride was associated with a significantly higher risk of suicide death compared to dutasteride, specifically in men with a history of mood disorders (Laanani et al., 2023). Conversely, pharmacovigilance analyses have identified safety signals for suicidality only with finasteride—not dutasteride—although this may reflect media-stimulated reporting. (Gupta et al., 2025; Nguyen et al., 2021)

Putting it in Perspective

Contemporaneous to the paper by Brezis (and likely why it wasn’t included in the review), a 2025 study examining real-world patient data found no increased risk of mood disorders—including depressive episode, major depressive disorder, persistent mood disorder, manic episode, bipolar disorder, and unspecified mood disorder—among men with androgenetic alopecia (AGA) treated with finasteride or dutasteride. By excluding patients with prior mood disorders, benign prostatic hyperplasia (BPH), or prior sexual dysfunction, the study aimed to isolate the effect in otherwise healthy hair-loss patients. The authors concluded that 5-alpha reductase inhibitors “were not associated with increased [mood-disorder] risk” in AGA treatment and that finasteride and dutasteride demonstrated “similar safety profiles” in this context. They suggest dermatologists can reassure hair-loss patients that mood symptoms arising during treatment are unlikely to be caused by finasteride.

I personally reviewed a large portion of the primary literature focusing on studies evaluating patients treated for androgenetic alopecia (summarized in the table below). Broadly, the available evidence does not support a definitive conclusion. While there does appear to be a statistical increase in mood disorders among patients taking 5-alpha reductase inhibitors—mainly finasteride—the absolute risk remains small: approximately one additional case of depression per 1,000–2,000 patients treated per year. Given that the baseline incidence of depression in the general population is roughly 5 cases per 1,000 people per year, this represents a relatively modest increase.

Study	Population (Size, Age, Indication, Medication, Dose)	Study Design	Outcome Measures & Key Statistics
Welk et al., 2017	- Number: 93,197 exposed men (matched to 93,197 unexposed) - Age: ≥ 66 years (Median: 75) - Indication: Benign Prostatic Hyperplasia - Meds/Dose: Finasteride 1mg or Dutasteride 0.5mg	Retrospective, matched cohort study (Ontario, Canada)	- Depression: Increased risk in first 18 months (HR 1.94; 95% CI 1.73–2.16), stabilizing at HR 1.22 thereafter - Suicide: No significant increase (HR 0.88; 95% CI 0.53–1.45) - Self-harm: Increased risk in first 18 months (HR 1.88; 95% CI 1.34–2.64) Bottom line: additional 1 case of depression per 420 patients taking finasteride/dutasteride per year
Lyakhovitsky et al., 2024	- BPH Group: 307 patients (Mean age 61.5) vs 1218 controls. (Finasteride 5mg) - AGA Group: 23,227 patients (Mean age 31.4) vs 39,444 controls. (Finasteride 1mg)	Population-based case-control study (Israel)	- BPH Group: No significant increase in psychiatric outcomes - AGA Group: Increased anxiety (0.6% vs 0.4%, p=0.04) and depression (0.5% vs 0.4%, p=0.007)  - Multivariate Analysis (AGA): OR 1.44 for anxiety, OR 1.43 for depression Bottom line: additional 1 case of depression per 2000 patients taking finasteride per year
Garcia-Argibay et al., 2022	- Number: 2,236,876 men (70,645 on Finasteride, 8,774 on Dutasteride) - Age: 50–90 years - Indication: BPH/Alopecia - Meds: Finasteride, Dutasteride (dose not provided)	Register-based cohort study (Sweden)	- Depression: Increased risk for Finasteride (HR 1.61) and Dutasteride (HR 1.68)  - Suicide: No significant association for Finasteride (HR 1.22; 95% CI 0.99–1.49) or Dutasteride (HR 0.98) - Dementia: Initial risk decreased over time (possible surveillance bias) Bottom line: additional ~1 cases of depression per 1000 patients taking finasteride/dutasteride per year
Neubauer et al., 2025	- Number: 355 Dutasteride, 25,703 Finasteride, 86,815 Controls - Age: Mean 36.9 (Dut), 34.7 (Fin), 29.1 (Controls) - Indication: AGA (BPH excluded) - Meds: Dutasteride (mean dose 0.5mg), Finasteride (mean dose 1.6mg)	Retrospective cohort database study (TriNetX, USA)	- Mood Disorders: No increased risk for Finasteride (HR 0.979; 95% CI 0.921–1.040) or Dutasteride (HR 1.255; 95% CI 0.768–2.051) compared to controls; No difference between Dutasteride and Finasteride (HR 1.216)
Nguyen et al., 2021	- Number: 3,282 adverse event reports in Finasteride users - Age: Mostly 18–44 years (70.9%) - Indication: Alopecia, BPH - Meds: Finasteride (vs Minoxidil, Tamsulosin, Dutasteride)	Pharmacovigilance case-noncase study (VigiBase, Global)	- Suicidality: Significant signal (ROR 1.63); stratification - Significant signals only in patients <45 years (ROR 3.47) and for Alopecia (ROR 2.06); no signal for BPH or older patients - Psychological AE: Significant signal (ROR 4.33); also driven by young, alopecia patients, but specific RORs not provided
Laanani et al., 2023	- Number: 69,786 Finasteride users vs 217,577 Dutasteride users - Age: Men ≥ 50 years (Median ~72) - Indication: BPH - Meds: Finasteride 5mg, Dutasteride 0.5mg	Nationwide cohort study (France)	- Overall Suicide/Self-harm: No significant difference between drugs (HR 1.21; 95% CI 0.87–1.67) - History of Mood Disorders Subgroup: Finasteride associated with higher risk of suicide death (HR 2.71; 95% CI 1.07–6.91) and severe self-harm vs Dutasteride - Overall suicide rate in study was ~2.5x general population Bottom line: did not evaluate depression; absolute suicide rate amounts to 1 additional case per 2000 patients per year in finasteride users with a history of mood disorders compared to dutasteride
Gupta et al., 2025	- Number: Millions of reports in FAERS database - Indication: AGA and BPH - Meds: Finasteride (1mg, 5mg), Dutasteride	Disproportionality analysis of FAERS data (USA)	- Finasteride (2006–2011): No significant signals - Finasteride (2013–2018): Signal for suicidal ideation (ROR 2.8) - Finasteride (2019–2023): Signal for suicidal ideation (ROR 5.0) - Dutasteride: No signals detected in any period Bottom line: reporting of suicidal ideation increased after 2011 up to a max of 5x more than expected in the 2019-2023 period

Rates of irreversible depression or other PFS-associated symptoms appear to be even more rare. This is not to diminish how distressing these cases are, or how life-altering the experience can be for patients who develop persistent adverse effects after taking finasteride or any other medication. But, stories of “finasteride nightmares” are rare, anecdotal, and largely unverifiable. The truth is, contending with rare, unpredictable, and unverified side effects for medications that potentially provide hundreds of thousands of other patients benefits is a difficult thing for doctors to contend with. I am not sure there is a good answer other than to make sure patients are informed of the possible risks and benefits. Broadly speaking, side effects from finasteride, if experienced, resolve in essentially all patients once the medication is discontinued, and persistent sexual side effects—such as those seen in PFS—occur in fewer than 1% of patients after stopping the drug; their connection to finasteride remains controversial (Mysore, 2012; Pereira, 2020). Suicide is similarly rare, but because it is a far more serious outcome, even small increases in incidence deserve close attention. Patients should be counseled—similar to isotretinoin users—that while the connection to finasteride remains rare and debated, any thoughts of self-harm must be promptly reported.

Patients also need to be aware of the nocebo effect, the tricky counterpart of the placebo effect. It occurs when a person experiences negative side effects from a treatment simply because they expect them to happen, not because the medication itself caused them. A 2007 study (Mondaini 2007) on finasteride demonstrated this. Patients were given 5mg finasteride and split into two groups: group A was explicitly told the drug could cause sexual side effects like erectile dysfunction (ED) and low libido–group B was not told about these specific side effects. The result? In group A (who were warned), 44% reported sexual side effects but in group B (who were not warned), only 15% reported them. The drug was exactly the same, but the expectation of harm nearly tripled the rate of reported side effects.

The studies I reviewed, many of which Brezis uses to draw conclusions in his review, also exhibit significant methodological limitations, especially the pharmacovigilance analyses. A primary concern is reporting bias or “stimulated reporting,” where media attention and public-awareness campaigns (including the founding of the Post-Finasteride Syndrome Foundation in 2012) artificially increase adverse-event reports. For example, both Gupta et al. and Nguyen et al. observed that safety signals for suicidality emerged only after 2012—coinciding with increased publicity—while no comparable signals were detected for pharmacologically similar drugs like dutasteride, which received less media attention. Additionally, pharmacovigilance databases such as FAERS and VigiBase lack a true denominator: researchers do not know the total number of people taking the drug, making it impossible to calculate actual incidence rates. Reports are also voluntary, unverified, and often incomplete, frequently missing details like dosage, duration, or psychiatric history—hindering efforts to establish causality.

Bottom Line

Ultimately, whether you feel comfortable taking a 5-alpha reductase inhibitor for hair loss is a highly personal decision. As someone currently unaffected by the condition, I struggle to answer the question many patients ask: “What would you do?” I typically tell patients that although the risk–benefit ratio is favorable, I personally do not place enough value on hair—and tend to be medication-averse—that I likely would not take anything for hair loss. However, for other conditions, I might be willing to incur a small theoretical risk in exchange for meaningful benefit–this may be how many feel about hairloss. My goal is to provide comprehensive safety and efficacy information, along with appropriate context, so that patients can make informed decisions.

In short, the risk of depression or sexual side effects from 5-alpha reductase inhibitors is low, though likely not zero. I encourage patients first to consider how important their hair loss is to their identity and well-being; if hair loss is causing significant anxiety or depression, counseling may be helpful to try an determine if the value and expectations one places around hair are healthy and proportionate, or if they are manifestation of other mental health pathology. Also, be aware of what real-world treatment outcomes look like—most hair-loss treatments yield modest improvements in hair thickness and growth. Dramatic results often represent misdiagnosed cases of telogen effluvium, a self-resolving condition, rather than true treatment effects. Finally, be cautious with services that offer quick, inexpensive or free evaluations tied to prescriptions; these companies profit from medication sales and therefore have an inherent bias toward recommending drug therapy over personalized, medically grounded guidance.

Dr. Ryan M. Trowbridge, MD, MS, MA

Harvard-Trained, Board-Certified Dermatologist and DermMythBuster

P.S. Have you come across any new or conflicting research on this topic? Please share—I’d love to explore it further with you!

For medical consultations with me, visit Bridge-Derm.com.

Citations

Brezis M. Failing Public Health Again? Analytical Review of Depression and Suicidality From Finasteride. J Clin Psychiatry. 2025 Sep 22;86(4):25nr15862. doi: 10.4088/JCP.25nr15862. PMID: 41004169.

Garcia-Argibay M, Hiyoshi A, Fall K, Montgomery S. Association of 5α-Reductase Inhibitors With Dementia, Depression, and Suicide. JAMA Netw Open. 2022 Dec 1;5(12):e2248135. doi: 10.1001/jamanetworkopen.2022.48135. PMID: 36547981; PMCID: PMC9857015.

Gupta AK, Bamimore MA, Williams G, Talukder M. Finasteride Use: Evaluation of Depression and Suicide Risk. J Cosmet Dermatol. 2025 Mar;24(3):e70102. doi: 10.1111/jocd.70102. PMID: 40082195; PMCID: PMC11906302.

Irwig MS. Depressive symptoms and suicidal thoughts among former users of finasteride with persistent sexual side effects. J Clin Psychiatry. 2012 Sep;73(9):1220-3. doi: 10.4088/JCP.12m07887. Epub 2012 Aug 7. PMID: 22939118.

Laanani M, Weill A, Jollant F, Zureik M, Dray-Spira R. Suicidal risk associated with finasteride versus dutasteride among men treated for benign prostatic hyperplasia: nationwide cohort study. Sci Rep. 2023 Mar 31;13(1):5308. doi: 10.1038/s41598-023-32356-3. PMID: 37002313; PMCID: PMC10066399.

Lyakhovitsky A, Amichai B, Galili E, Cohen A, Kridin K, Segal Z, Netzer D. The risk of psychiatric disorders in finasteride users with benign prostatic hyperplasia and androgenetic alopecia: A population-based case-control study. Australas J Dermatol. 2024 Dec;65(8):621-629. doi: 10.1111/ajd.14359. Epub 2024 Aug 13. PMID: 39138902.

Mondaini N, Gontero P, Giubilei G, Lombardi G, Cai T, Gavazzi A, Bartoletti R. Finasteride 5 mg and sexual side effects: how many of these are related to a nocebo phenomenon? J Sex Med. 2007 Nov;4(6):1708-12. doi: 10.1111/j.1743-6109.2007.00563.x. Epub 2007 Jul 26. PMID: 17655657.

Mysore V. Finasteride and sexual side effects. Indian Dermatol Online J. 2012 Jan;3(1):62-5. doi: 10.4103/2229-5178.93496. PMID: 23130269; PMCID: PMC3481923.

Neubauer Z, Ong MM, Lipner SR. No increased risk of mood disorders in male androgenetic alopecia patients treated with dutasteride and finasteride: A retrospective cohort database study. J Am Acad Dermatol. 2025 Jul;93(1):197-199. doi: 10.1016/j.jaad.2025.03.068. Epub 2025 Mar 28. PMID: 40158535.

Nguyen DD, Marchese M, Cone EB, Paciotti M, Basaria S, Bhojani N, Trinh QD. Investigation of Suicidality and Psychological Adverse Events in Patients Treated With Finasteride. JAMA Dermatol. 2021 Jan 1;157(1):35-42. doi: 10.1001/jamadermatol.2020.3385. PMID: 33175100; PMCID: PMC7658800.

Pereira AFJR, Coelho TOA. Post-finasteride syndrome. An Bras Dermatol. 2020 May-Jun;95(3):271-277. doi: 10.1016/j.abd.2020.02.001. Epub 2020 Mar 25. PMID: 32317131; PMCID: PMC7253896.

Welk B, McArthur E, Ordon M, Anderson KK, Hayward J, Dixon S. Association of Suicidality and Depression With 5α-Reductase Inhibitors. JAMA Intern Med. 2017 May 1;177(5):683-691. doi: 10.1001/jamainternmed.2017.0089. PMID: 28319231; PMCID: PMC5818776.