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Hormone · Profile

Finasteride

Propecia · Proscar · 5-alpha reductase inhibitor

Hormone ManagementApproved
MW
372.5g/mol
Formula
C23H36N2O2

Finasteride is a synthetic 5α-reductase inhibitor that primarily acts on the type II isoenzyme, reducing the conversion of testosterone to dihydrotestosterone (DHT) in the body, particularly in the scalp and prostate. Researchers primarily study finasteride for its effects on androgenetic alopecia (AGA) and benign prostatic hyperplasia. Key findings from clinical studies indicate that finasteride can significantly increase total hair count in men with AGA compared to placebo, but it is also associated with adverse effects, including sexual dysfunction and potential psychiatric symptoms such as depression. Current research continues to explore the safety profile of finasteride, particularly regarding the persistence of side effects after discontinuation, highlighting its clinical relevance in managing conditions linked to androgen levels.

Overview

Übersicht

Finasteride is a synthetic compound classified as a 5-alpha reductase inhibitor. It is not an endogenous hormone but is chemically synthesized for therapeutic purposes. Finasteride is primarily used in the management of androgen-dependent conditions such as androgenetic alopecia (AGA) and benign prostatic hyperplasia (BPH). It is marketed under brand names like Propecia and Proscar. Researchers have found that finasteride effectively reduces the levels of dihydrotestosterone (DHT), a potent androgen involved in hair loss and prostate enlargement. The primary physiological role of finasteride is to inhibit the conversion of testosterone to DHT by targeting the 5-alpha reductase enzyme, specifically the type II isoenzyme. This action results in decreased DHT levels, which is beneficial in conditions like AGA and BPH. Finasteride's mechanism of action involves the inhibition of the 5-alpha reductase enzyme, which prevents the conversion of testosterone into dihydrotestosterone (DHT). This reduction in DHT levels leads to decreased androgenic activity in tissues such as the scalp and prostate, thereby mitigating hair loss and reducing prostate size. Pharmacokinetically, finasteride has an oral bioavailability, with a plasma half-life of approximately 4.5 hours. It is metabolized primarily in the liver and excreted in urine and feces. Clinically, finasteride is approved by the FDA for the treatment of male pattern hair loss and BPH. It is available in oral formulations, with 1 mg/day commonly prescribed for AGA and 5 mg/day for BPH. Despite its efficacy, researchers have observed side effects such as sexual dysfunction and potential neuropsychiatric effects, which have been noted in post-marketing surveillance and led to updates in safety labeling.

Chemical profile

Chemische Struktur

Chemical structure of Finasteride
FormelC23H36N2O2
Molekulargewicht372.5g/mol
CAS-Nummer98319-26-7
PubChem CID57363
Mechanism

Wirkmechanismus

Finasteride acts by inhibiting the 5-alpha reductase enzyme, specifically the type II isoenzyme, which is responsible for converting testosterone into dihydrotestosterone (DHT). This inhibition results in decreased DHT levels, reducing androgenic effects in tissues such as the scalp and prostate.

Mechanism

Signalweg

Finasteride acts as a competitive inhibitor of the 5α-reductase (5AR) enzyme, specifically the type II isoenzyme, which catalyzes the conversion of testosterone to dihydrotestosterone (DHT), a potent androgen that binds to androgen receptors and activates androgen receptor signaling pathways involved in hair follicle miniaturization in androgenetic alopecia. By reducing DHT levels in serum and scalp, finasteride disrupts this signaling, leading to decreased hair loss and potentially promoting hair regrowth. The full mechanism of action, particularly regarding its neuropsychiatric side effects, is not completely understood.

Half-Life & Pharmacokinetics

POOral

Plasma half-life ~4.5 hours

Finasteride is primarily metabolized in the liver and excreted in urine and feces.

Storage

Temperature

Store at room temperature (15-30C)

Light

Protect from light

Form

Stable in tablet form

Notes

Avoid exposure to moisture.

Solubility

Löslichkeit

Finasteride is poorly soluble in water but soluble in organic solvents like ethanol and chloroform.

Legal Status

🇩🇪DE

Prescription only (verschreibungspflichtig), not a controlled substance under BtMG.

🇺🇸US

FDA-approved for AGA and BPH, prescription required.

🇦🇺AU

TGA Schedule 4 (prescription only medicine).

🇬🇧UK

Prescription only medicine (POM) under MHRA.

Legal status information is provided for general reference only and may not reflect the most current regulatory changes. Always verify with official government sources before making any decisions.

Open Questions

Offene Forschungsfragen

Current evidence is limited regarding the long-term psychiatric effects of finasteride, particularly the persistence of depression and suicidal ideation after discontinuation, necessitating larger longitudinal studies to better understand these risks. Additionally, there is a need for more comprehensive research on the sexual side effects associated with different dosages and formulations of finasteride, including comparisons with dutasteride, to clarify the incidence and severity of these adverse effects in diverse populations. Further research is needed to explore the pharmacokinetics and pharmacodynamics of topical finasteride versus oral formulations, particularly in terms of systemic exposure and long-term safety profiles.

61 Research Publications

4,351

Total Citations

26

Human/RCT

6.9

Avg. Influence

2023

Latest

Sort
Filter
#01

The long-term effect of doxazosin, finasteride, and combination therapy on the clinical progression of benign prostatic hyperplasia.

HumanInfluence88.0
1881
The study demonstrated that finasteride significantly reduced the risk of clinical progression of benign prostatic hyperplasia in human males over a long-term follow-up.
#02

Finasteride in the treatment of men with androgenetic alopecia. Finasteride Male Pattern Hair Loss Study Group.

Kaufman K D, et al. · Journal of the American Academy of Dermatology · 1998

HumanInfluence17.0
602
The study demonstrated that finasteride treatment significantly increased scalp hair count in human males with androgenetic alopecia over one and two years compared to placebo.

Key findings

  1. 01Finasteride treatment led to a significant increase in hair count after one and two years.
  2. 02Men taking finasteride reported improvements in hair growth and appearance.
  3. 03Minimal adverse effects were noted during the study.
#03

The effects of finasteride on scalp skin and serum androgen levels in men with androgenetic alopecia.

HumanInfluence12.0
207
The study demonstrated that finasteride significantly decreased both scalp skin and serum DHT levels in human males with androgenetic alopecia.
#04

Depressive symptoms and suicidal thoughts among former users of finasteride with persistent sexual side effects.

Case ReportInfluence7.0
167
The study demonstrated that former users of finasteride with persistent sexual side effects exhibited significantly higher rates of depressive symptoms and suicidal thoughts compared to controls.
#05

Clinical pharmacokinetics and pharmacodynamics of finasteride.

ReviewInfluence5.0
114
The study demonstrated that finasteride effectively reduces dihydrotestosterone levels and prostate size, but its correlation with symptom improvement in benign prostatic hyperplasia remains limited.
#06

Efficacy and safety of topical finasteride spray solution for male androgenetic alopecia: a phase III, randomized, controlled clinical trial.

Piraccini B M, et al. · Journal of the European Academy of Dermatology and Venereology : JEADV · 2022

HumanInfluence6.0
111
Researchers observed that topical finasteride significantly improved hair count compared to placebo and had a similar effect to oral finasteride with lower systemic exposure in human males with androgenetic alopecia.

Key findings

  1. 01Topical finasteride increased hair count more than placebo after 24 weeks.
  2. 02The side effects of topical finasteride were similar to those of the placebo.
  3. 03Topical finasteride had much lower levels of systemic exposure than oral finasteride.
#07

Comparison of oral minoxidil, finasteride, and dutasteride for treating androgenetic alopecia.

Gupta Aditya K, et al. · The Journal of dermatological treatment · 2022

ReviewInfluence9.0
94
Researchers observed that dutasteride was more effective than finasteride for androgenetic alopecia, with both drugs showing similar safety profiles.

Key findings

  1. 01Dutasteride is probably the most effective treatment for androgenetic alopecia.
  2. 02Finasteride is FDA-approved, while minoxidil and dutasteride are used off-label.
  3. 03Minoxidil can cause excessive hair growth and cardiovascular issues, while finasteride and dutasteride may lead to sexual side effects.
#08

Investigation of Suicidality and Psychological Adverse Events in Patients Treated With Finasteride.

Case ReportInfluence5.0
92
Researchers observed significant signals for suicidality and psychological adverse events associated with finasteride use, particularly in younger patients with alopecia.
#09

Comparison of finasteride (Proscar) and Serenoa repens (Permixon) in the inhibition of 5-alpha reductase in healthy male volunteers.

Human
76
The study demonstrated that finasteride significantly reduces serum dihydrotestosterone levels compared to placebo, confirming its efficacy as a 5-alpha reductase inhibitor in healthy male volunteers.
#10

Finasteride for hair loss: a review.

Gupta A K, et al. · The Journal of dermatological treatment · 2022

HumanInfluence2.0
74
The study demonstrated that finasteride 1 mg/day significantly increased total hair count compared to placebo after 24 and 48 weeks in human males with androgenetic alopecia.

Key findings

  1. 01Finasteride 1 mg/day significantly increases total hair count after 24 weeks.
  2. 02The review covers how finasteride functions and is processed in the body.
  3. 03Potential side effects and post-marketing reports were also discussed.

Clinical Trials (30)

Preclinical
Phase I
Phase II
Phase III
Approved

30

Total Trials

58,428

Total Enrolled

Establishing the Benefits of Adherence to Enlarged Prostate Treatment: A Validation Study Linking Adherence to Outcomes Using the Market Scan Database

NCT01381510COMPLETED
Sponsor

GlaxoSmithKline

Enrollment

54,459

Started

2010

Primary outcome

The occurence of a diagnosis code for acute urinary retention (AUR) or a procedure code for prostate surgery

Prostatic Hyperplasia

Topical Finasteride in the Treatment of Idiopathic Hirsutism

NCT00564252COMPLETED
Sponsor

Iran University of Medical Sciences

Enrollment

56

Started

2006

Primary outcome

the efficacy of topical finasteride was determined by comparison of Ferriman-Gallwey score before and after medication

Idiopathic Hirsutism

High Risk Prostate Cancer Prevention Study

NCT01174953COMPLETED
Sponsor

University of Kansas

Enrollment

18

Started

2010

Primary outcome

Biomarkers will be identified to help predict future prostate cancer risks and patients likely to benefit from preventive strategies

Prostate Cancer

Advanced Benefits of Alpha-blocker Monotherapy on Lower Urinary Tracts Symptoms(LUTS) Patients

NCT01736033Phase 4UNKNOWN
Sponsor

Seoul National University Hospital

Enrollment

545

Started

2012

Primary outcome

Clinical Progression

Benign Prostate Hyperplasia

Study to Evaluate the Therapeutic Action of Tamsulosin and Finasteride in Symptomatic Benign Prostatic Hyperplasia (BPH) Patients

NCT02244229Phase 4COMPLETED
Sponsor

Boehringer Ingelheim

Enrollment

403

Started

1998

Primary outcome

Change from baseline in Symptom Problem Index (SPI) by means of validated patient questionnaire

Prostatic Hyperplasia

3 Month Finasteride Challenge Test Can Significantly Improve the Performance of Screening for Prostate Cancer

NCT01296672Phase 4COMPLETED
Sponsor

The University of Texas Health Science Center at San Antonio

Enrollment

383

Started

2011

Primary outcome

Pre/Post Ratio PSA Area Under the Curve (AUC)

Prostate Cancer

Kinetics of the Finasteride Prostate Induced Apoptosis

NCT00130767Phase 4UNKNOWN
Sponsor

Hospices Civils de Lyon

Enrollment

90

Started

2004

Primary outcome

Date of the maximum apoptosis in the prostate tissues treated by finasteride

Benign Prostatic Hyperplasia

Study to Evaluate the Efficacy and Safety of P-3074 Topical Solution in the Treatment of Androgenetic Alopecia

NCT03004469Phase 3COMPLETED
Sponsor

Polichem S.A.

Enrollment

458

Started

2016

Primary outcome

Adjusted Mean Change From Baseline in Hair Growth Assessed by Target Area Hair Count (TAHC) in the Vertex at Week 24

Alopecia, Androgenetic

Evaluate the Efficacy and Safety of GV1001 in Patients With Benign Prostatic Hyperplasia (BPH)

NCT04032067Phase 3COMPLETED
Sponsor

GemVax & Kael

Enrollment

423

Started

2019

Primary outcome

Change in International Prostate Symptom Score(IPSS)

Benign Prostatic Hyperplasia (BPH)

Efficacy and Safety of Finlândia Hair Lotion Association on Androgenetic Alopecia

NCT04594018Phase 3RECRUITING
Sponsor

EMS

Enrollment

190

Started

2023

Primary outcome

Change from baseline in hair density.

Androgenetic Alopecia

Comparison of Finasteride and Tamsulosin for Treatment of Benign Prostatic Hyperplasia (BPH) (MK-0906A-149 AM2)

NCT01534351Phase 3TERMINATED
Sponsor

Merck Sharp & Dohme LLC

Enrollment

1

Started

2013

Primary outcome

Change From Baseline in International Prostate Symptom Score (IPSS)

Benign Prostatic Hyperplasia

Finasteride and Flutamide in Pre-surgical Trial in Prostate Cancer.

NCT06601205Phase 2/3COMPLETED
Sponsor

Ente Ospedaliero Ospedali Galliera

Enrollment

125

Started

2004

Primary outcome

Change of Nuclear area size

Prostate CancerProstatic Intraepithelial Neoplasia

Effectiveness and Safety of Topical Finasteride and Minoxidil Combination Compared to Topical Minoxidil for The Treatment of Male Androgenetic Alopecia

NCT05990400Phase 2/3UNKNOWN
Sponsor

Indonesia University

Enrollment

40

Started

2023

Primary outcome

Hair density

Androgenetic Alopecia

New Treatment Strategies and Epigenetic Biomarker for Management of Benign Prostatic Hyperplasia

NCT06944145Phase 2RECRUITING
Sponsor

Beth Israel Deaconess Medical Center

Enrollment

242

Started

2025

Primary outcome

Clinical response to at 12 months after study enrollment

BPH (Benign Prostatic Hyperplasia)Lower Urinary Track Symptoms

Finasteride in Treating Patients With Stage II Prostate Cancer Who Are Undergoing Surgery

NCT00438464Phase 2COMPLETED
Sponsor

National Cancer Institute (NCI)

Enrollment

204

Started

2007

Primary outcome

Comparison of Biomarkers Between Treatment Arms: Percentage Change of Tumor Cells Exhibiting Detectable Staining Within Gleason Grade 3 (GG3) Biomarker Subgroups at Prostatectomy

Adenocarcinoma of the ProstateStage II Prostate Cancer

Various Procedural Treatment Options for Androgenetic Alopecia

NCT06826001Phase 2NOT_YET_RECRUITING
Sponsor

Sheikh Zayed Medical College

Enrollment

190

Started

2025

Primary outcome

COMPARISON OF EFFICACY OF TOPICAL FINESTERIDE VERSUS TOPICAL MINOXIDAL IN TREATMENT OF ANDROGENETIC ALOPECIA

Androgenetic Alopecia

Clinical Trial to Evaluate CG2001 in Chinese Adult Male Participants With Androgenetic Alopecia

NCT07076706Phase 2COMPLETED
Sponsor

Beijing Dayspring Pharmaceutical Technology Co., Ltd

Enrollment

110

Started

2024

Primary outcome

Change from baseline in the non-vellus target area hair count(TAHC) at 24 weeks

Male Pattern of Hair Loss, Androgenic AlopeciaAndrogenetic Alopecia (AGA)

Hormone Therapy in Treating Patients With Prostate Cancer

NCT00003323Phase 2COMPLETED
Sponsor

Alliance for Clinical Trials in Oncology

Enrollment

101

Started

1998

Primary outcome

PSA levels

Prostate CancerSexual Dysfunction and Infertility

Phase 2 Study of NX-1207 for the Treatment of Benign Prostatic Hyperplasia (BPH) (Enlarged Prostate)

NCT00759135Phase 2COMPLETED
Sponsor

Nymox Corporation

Enrollment

85

Started

2007

Primary outcome

Change in BPH Symptom Score (AUA SI)

Benign Prostatic Hyperplasia (BPH)Enlarged Prostate

Neoadjuvant Finasteride for Patients With Non-small Cell Lung Cancer

NCT02055170Phase 2TERMINATED
Sponsor

CancerCare Manitoba

Enrollment

4

Started

2014

Primary outcome

Change in proliferation

Non-small Cell Lung Cancer

A Clinical Trial to Assess Pharmacokinetic/Pharmacodynamic Profiles and Safety of IVL3001

NCT04945226Phase 1/2COMPLETED
Sponsor

Inventage Lab., Inc.

Enrollment

40

Started

2021

Primary outcome

AUClast of IVL3001

Androgenetic Alopecia

Pilot Study for the Evaluation of Finasteride in the Treatment of Chronic Central Serous Chorioretinopathy

NCT00837252Phase 1/2COMPLETED
Sponsor

National Eye Institute (NEI)

Enrollment

5

Started

2009

Primary outcome

Change in Visual Acuity at Month 3 Compared to Baseline.

Retinal Disease

Extension Study for the Evaluation of Finasteride in the Treatment of Chronic Central Serous Chorioretinopathy

NCT01227993Phase 1/2COMPLETED
Sponsor

National Eye Institute (NEI)

Enrollment

3

Started

2010

Primary outcome

Change in Best-corrected Visual Acuity (BCVA) in the Study Eye at Two Years Compared to Baseline

Retinal Disease

Study to Evaluate Safety & Usability of a New Formulation for Male Androgenetic Alopecia

NCT05611593Phase 1UNKNOWN
Sponsor

Follicle Pharma Ltd

Enrollment

90

Started

2022

Primary outcome

Safety of product application

Androgenic Alopecia

Study to Evaluate the Drug-drug Interaction Between IY001 and IY002 in Healthy Adult Male Subjects.

NCT07322991Phase 1COMPLETED
Sponsor

Il-Yang Pharm. Co., Ltd.

Enrollment

43

Started

2025

Primary outcome

Finasteride Area Under the Curve during the dosing interval at steady state (AUCτ,ss)

Healthy Adult Male

Fed Study of Finasteride Tablets 5 mg and Proscar® Tablets 5 mg

NCT00650377Phase 1COMPLETED
Sponsor

Mylan Pharmaceuticals Inc

Enrollment

30

Started

2004

Primary outcome

Bioequivalence

Healthy

Bioequivalence Study of Finasteride 5 mg Tablet Formulations Under Fasting Conditions

NCT01264289Phase 1COMPLETED
Sponsor

Dr. Reddy's Laboratories Limited

Enrollment

26

Started

2006

Primary outcome

Bioequivalence based on Cmax and AUC parameters

Healthy

Bioequivalence Study of Two Finasteride 5 mg Tablet Formulations Under Non-Fasting Conditions

NCT01264302Phase 1COMPLETED
Sponsor

Dr. Reddy's Laboratories Limited

Enrollment

26

Started

2006

Primary outcome

Bioequivalence based on Cmax and AUC parameters

Healthy

PK Comparison of GL2701 With Finasteride and Tamsulosin in Combination

NCT01829893Phase 1COMPLETED
Sponsor

Korea University Anam Hospital

Enrollment

26

Started

2012

Primary outcome

Finasteride and Tamsulosin pharmacokinetics (Cmax and AUC)

Benign Prostatic Hyperplasia (BPH)

Association of Polymorphisms in the Androgen Receptor Gene and Finasteride Response in Women With Androgenetic Alopecia

NCT01052870Phase 1COMPLETED
Sponsor

HairDx, LLC

Enrollment

12

Started

2008

Androgenetic Alopecia

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Legal Disclaimer

This page is for informational and research purposes only. All information is based on published scientific literature and does not constitute medical advice, diagnosis, or treatment recommendations. Many substances listed may not be approved for human use and may be subject to drug regulation laws (e.g., AMG in Germany, FDA in the US). PepStack does not encourage the use of any substance on humans. Always consult a qualified healthcare professional before making any health-related decisions. Use of this information is entirely at your own risk. PepStack assumes no liability for the accuracy, completeness, or timeliness of the content provided. Full disclaimer