Finasteride and Depression: A Review of the Evidence

This research hub summarizes the clinical evidence base on finasteride and psychiatric adverse effects, focusing on depression and suicidal ideation. This is a topic of active regulatory interest and was the subject of an EMA 2019 label update. Evidence quality varies substantially across the studies.

Key Evidence Landmarks

Publication/Event	Year	Design	Key Finding
Hogan C et al. (Psychother Psychosom)	2014	Case series	Series of PFS cases including men with new-onset depression without prior psychiatric history; documented temporal relationship to finasteride
Melcangi RC et al. neurosteroid studies	2014–2017	Controlled laboratory/clinical cohort	Reduced allopregnanolone (a GABA-A positive modulator with anxiolytic/antidepressant properties) in serum and CSF of finasteride-exposed individuals; provides plausible neurobiological mechanism for mood effects
EMA PRAC review and label update	2019	Regulatory signal assessment	European Medicines Agency recommended adding depression and suicidal ideation to Propecia/Proscar prescribing information for the EU following review of spontaneous adverse event reports
Dillon KH et al. (JAMA Dermatol)	2020	Cross-sectional survey; PFS foundation database	73.9% of self-reported PFS patients endorsed depression; suicidal ideation present in 35.9%; limitations include selection bias of self-selected PFS registry participants
Dyson TE et al. (J Urol)	2020	Retrospective insurance database cohort	No statistically significant increase in depression diagnosis rates in finasteride users vs. matched controls in administrative claims analysis; contrasts with registry data

Evidence Quality Assessment

• Depression as an adverse effect: Regulatory acknowledgment (FDA, EMA labeling) that it can occur; biologically plausible via neurosteroid mechanism; moderate-strength signal from case series and registry data
• Frequency: Not established in general-population studies; selection bias is a major limitation in most high-signal studies
• Suicidal ideation: Present in case series and registry data; EMA label includes it; no prospective population RCT confirms incidence vs. placebo
• Mechanism: Neurosteroid hypothesis (reduced allopregnanolone) is plausible and supported by in-vitro and cohort data, but not confirmed by intervention trial

For full clinical context: Finasteride and depression | Post-Finasteride Syndrome

Sources

• Dillon KH, et al. “Characteristics of men who report persistent sexual symptoms after finasteride use for hair loss.” JAMA Dermatol. 2020;156(6):693–695.
• European Medicines Agency. PRAC recommendations on signals — finasteride. November 2019.
• Melcangi RC, et al. “Neuroactive steroid levels are modified in cerebrospinal fluid and plasma of post-finasteride patients showing persistent sexual side effects and anxious/depressive symptomatology.” J Sex Med. 2013;10(10):2598–2603.