Adverse Effects of 5α-Reductase Inhibitors: What Do We Know, Don't Know, and Need to Know?

August 2015 in “ Reviews in Endocrine and Metabolic Disorders ”

Abdulmaged M. Traish, Roberto Cosimo Melcangi, Marco Bortolato, Luis Miguel García‐Segura, Michael Zitzmann

5α-reductase inhibitors finasteride dutasteride androgenetic alopecia benign prostatic hyperplasia erectile dysfunction testosterone tamsulosin nocebo effect Propecia Avodart BPH

TLDR 5α-reductase inhibitors may cause persistent sexual dysfunction and depression, needing more research on long-term effects.

The document reviewed the adverse effects of 5α-reductase inhibitors, such as finasteride and dutasteride, used for treating benign prostatic hyperplasia and androgenetic alopecia. It highlighted concerns about persistent sexual dysfunction, depression, and other non-sexual side effects in some users. Studies indicated that finasteride might lead to more severe erectile dysfunction and lower testosterone levels compared to tamsulosin. Additionally, there were discussions on the potential nocebo effect contributing to reported sexual side effects. The document emphasized the need for further research to fully understand the long-term impacts and mechanisms behind these adverse effects.

View this study on link.springer.com →

Discuss this study in the Community →

Research cited in this study

60 / 60 results

research Persistent Sexual Dysfunction and Suicidal Ideation in Young Men Treated with Low-Dose Finasteride: A Pharmacovigilance Study

69 citations , July 2015 in “Pharmacotherapy”

Low-dose finasteride may cause lasting sexual dysfunction and suicidal thoughts in young men.

Finasteride, Not Tamsulosin, Increases Severity of Erectile Dysfunction and Decreases Testosterone Levels in Men With Benign Prostatic Hyperplasia

research Finasteride, Not Tamsulosin, Increases Severity of Erectile Dysfunction and Decreases Testosterone Levels in Men With Benign Prostatic Hyperplasia

20 citations , June 2015 in “Hormone Molecular Biology and Clinical Investigation”

Finasteride worsens erectile dysfunction and lowers testosterone in men with enlarged prostates, unlike tamsulosin.

research Adverse Event Reporting in Clinical Trials of Finasteride for Androgenic Alopecia: A Meta-Analysis

44 citations , April 2015 in “PubMed”

Finasteride for hair loss may cause long-lasting side effects like impotence and low libido, but trials lack proper safety reporting.

research Finasteride and the Uncertainties of Establishing Harms

7 citations , April 2015 in “JAMA Dermatology”

Finasteride's potential harms are hard to accurately measure.

research Persistent Sexual Dysfunction and Depression in Finasteride Users for Male Pattern Hair Loss: A Serious Concern or Red Herring?

10 citations , December 2014 in “PubMed”

Finasteride, a hair loss drug, may cause sexual dysfunction and depression, but these effects are usually temporary and the drug is generally safe. More research is needed.

research Emerging Treatments in Alopecia

47 citations , October 2014 in “Expert Opinion on Emerging Drugs”

New alopecia treatments aim for better results and fewer side effects.

5α-Reductase Inhibitors Alter Steroid Metabolism and May Contribute to Insulin Resistance, Diabetes, Metabolic Syndrome, and Vascular Disease: A Medical Hypothesis

research 5α-Reductase Inhibitors Alter Steroid Metabolism and May Contribute to Insulin Resistance, Diabetes, Metabolic Syndrome, and Vascular Disease: A Medical Hypothesis

15 citations , October 2014 in “Hormone Molecular Biology and Clinical Investigation”

Some hair loss and prostate drugs might increase the risk of diabetes and heart disease.

research 5α-Reductase Inhibitors in Androgenetic Alopecia

29 citations , September 2014 in “Current Opinion in Endocrinology, Diabetes and Obesity”

Finasteride and dutasteride effectively treat hair loss in men and women, but may cause side effects like low libido and depression.

research 5α-Reductase Type 1 Deficiency or Inhibition Predisposes to Insulin Resistance, Hepatic Steatosis, and Liver Fibrosis in Rodents

93 citations , September 2014 in “Diabetes”

Lack of 5α-Reductase type 1 can lead to insulin resistance and liver problems.

research Androgen Levels and Semen Parameters Among Former Users of Finasteride With Persistent Sexual Adverse Effects

15 citations , September 2014 in “JAMA Dermatology”

A Population-Based Nested Case-Control Study: The Use of 5-Alpha-Reductase Inhibitors and the Increased Risk of Osteoporosis Diagnosis in Patients with Benign Prostate Hyperplasia

research A Population-Based Nested Case-Control Study: The Use of 5-Alpha-Reductase Inhibitors and the Increased Risk of Osteoporosis Diagnosis in Patients with Benign Prostate Hyperplasia

22 citations , August 2014 in “Clinical endocrinology”

Taking finasteride for benign prostate hyperplasia may increase the risk of osteoporosis, especially at higher doses.

Immunohistochemical Evaluation of Androgen Receptor and Nerve Structure Density in Human Prepuce from Patients with Persistent Sexual Side Effects after Finasteride Use for Androgenetic Alopecia

research Immunohistochemical Evaluation of Androgen Receptor and Nerve Structure Density in Human Prepuce from Patients with Persistent Sexual Side Effects after Finasteride Use for Androgenetic Alopecia

36 citations , June 2014 in “PLOS ONE”

Finasteride, a hair loss drug, may cause long-term sexual side effects due to changes in hormone receptor levels.

Patients Treated for Male Pattern Hair Loss with Finasteride Show Altered Levels of Neuroactive Steroids in Cerebrospinal Fluid and Plasma After Discontinuation

research Patients Treated for Male Pattern Hair Loss with Finasteride Show Altered Levels of Neuroactive Steroids in Cerebrospinal Fluid and Plasma After Discontinuation

61 citations , April 2014 in “The Journal of Steroid Biochemistry and Molecular Biology”

Finasteride affects brain and blood steroids, causing lasting sexual and emotional side effects.

A Randomized, Active- and Placebo-Controlled Study of the Efficacy and Safety of Different Doses of Dutasteride Versus Placebo and Finasteride in the Treatment of Male Subjects with Androgenetic Alopecia

research A Randomized, Active- and Placebo-Controlled Study of the Efficacy and Safety of Different Doses of Dutasteride Versus Placebo and Finasteride in the Treatment of Male Subjects with Androgenetic Alopecia

97 citations , January 2014 in “Journal of The American Academy of Dermatology”

Dutasteride 0.5 mg works better than finasteride and placebo for increasing hair in men with hair loss.

research The Dark Side of 5α-Reductase Inhibitors' Therapy: Sexual Dysfunction, High Gleason Grade Prostate Cancer, and Depression

75 citations , January 2014 in “Korean Journal of Urology”

5α-reductase inhibitors can cause sexual problems, higher risk of aggressive prostate cancer, and depression.

research Persistent Sexual and Nonsexual Adverse Effects of Finasteride in Younger Men

24 citations , December 2013 in “Sexual medicine reviews”

Finasteride can cause sexual problems and depression in young men.

research Organic Causes of Erectile Dysfunction in Men Under 40

2152 citations , November 2013 in “Urologia Internationalis”

Many men under 40 with erectile dysfunction have organic causes like vascular issues, medication side effects, or hormonal problems.

Long-Term Oral Administration of 5α-Reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

research Long-Term Oral Administration of 5α-Reductase Inhibitor Attenuates Erectile Function by Inhibiting Autophagy and Promoting Apoptosis of Smooth Muscle Cells in Corpus Cavernosum of Aged Rats

34 citations , September 2013 in “Urology”

Long-term use of a certain medication can worsen erectile function in aged rats by damaging penile muscle cells.

research Central 5-Alpha Reduction of Testosterone Is Required for Testosterone's Inhibition of the Hypothalamo-Pituitary-Adrenal Axis Response to Restraint Stress in Adult Male Rats

51 citations , July 2013 in “Brain Research”

Testosterone needs to be converted to DHT to reduce stress response in male rats.

research The Implication of Neuroactive Steroids in Tourette's Syndrome Pathogenesis: A Role for 5α-Reductase?

24 citations , June 2013 in “Journal of neuroendocrinology”

Neuroactive steroids and the enzyme 5α-reductase might be involved in the development of Tourette's syndrome.

The Efficacy and Safety of 5α-Reductase Inhibitors in Androgenetic Alopecia: A Network Meta-Analysis and Benefit–Risk Assessment of Finasteride and Dutasteride

research The Efficacy and Safety of 5α-Reductase Inhibitors in Androgenetic Alopecia: A Network Meta-Analysis and Benefit–Risk Assessment of Finasteride and Dutasteride

66 citations , June 2013 in “Journal of Dermatological Treatment”

Finasteride and dutasteride effectively treat hair loss, but may cause side effects like sexual dysfunction and depression.

research Dutasteride for the Treatment of Benign Prostatic Hyperplasia

24 citations , June 2013 in “Expert opinion on pharmacotherapy”

Dutasteride effectively treats benign prostatic hyperplasia but isn't approved for preventing prostate cancer.

research 5-Alpha Reductase Inhibitors in Prostate Cancer: From Clinical Trials to Clinical Practice

7 citations , January 2013 in “European Urology”

5-Alpha reductase inhibitors may prevent prostate cancer but are not widely used due to concerns about trial relevance and potential risks, and more research is needed to confirm long-term benefits.

research Allopregnanolone-Mediated Protective Effects of Progesterone on Tributyltin-Induced Neuronal Injury in Rat Hippocampal Slices

43 citations , December 2012 in “The Journal of Steroid Biochemistry and Molecular Biology”

Progesterone protects neurons from damage by converting to allopregnanolone, which works through GABAA receptors.

research Depressive Symptoms and Suicidal Thoughts Among Former Users of Finasteride With Persistent Sexual Side Effects

134 citations , August 2012 in “The Journal of Clinical Psychiatry”

Former finasteride users with persistent sexual side effects have higher rates of depression and suicidal thoughts.

research 5α-Reductases in Human Physiology: An Unfolding Story

44 citations , July 2012 in “Endocrine Practice”

We need to learn more about 5α-reductases and neuroactive steroids to safely make drugs targeting these enzymes.

research Incomplete Recovery of Erectile Function in Rats After Discontinuation of Dual 5-Alpha Reductase Inhibitor Therapy

29 citations , July 2012 in “The Journal of Sexual Medicine”

Rats had lasting erectile problems after stopping a certain medication.

research Finasteride Attenuates Pathological Gambling in Patients With Parkinson's Disease

35 citations , April 2012 in “Journal of Clinical Psychopharmacology”

Finasteride reduces gambling symptoms in Parkinson's patients.

Effect of Testosterone Supplementation With and Without a Dual 5α-Reductase Inhibitor on Fat-Free Mass in Men With Suppressed Testosterone Production

research Effect of Testosterone Supplementation With and Without a Dual 5α-Reductase Inhibitor on Fat-Free Mass in Men With Suppressed Testosterone Production

124 citations , March 2012 in “JAMA”

Testosterone's muscle-building effects do not require its conversion to DHT.

research The 5 Alpha-Reductase Isozyme Family: A Review of Basic Biology and Their Role in Human Diseases

218 citations , December 2011 in “Advances in Urology”

The document concludes that the 5 alpha-reductase enzymes are important in steroid metabolism and related to various human diseases, with inhibitors used to treat conditions like male pattern baldness and prostate issues.

research Inhibition of 5α-Reductase in the Nucleus Accumbens Counters Sensorimotor Gating Deficits Induced by Dopaminergic Activation

53 citations , October 2011 in “Psychoneuroendocrinology”

Finasteride may help improve certain brain function issues linked to dopamine.

research The Risks and Benefits of 5α-Reductase Inhibitors for Prostate Cancer Prevention

147 citations , June 2011 in “New England journal of medicine/The New England journal of medicine”

5α-reductase inhibitors may prevent prostate cancer but could also raise the risk of more severe cancers.

research A Preliminary Study of Finasteride in Tourette Syndrome

46 citations , May 2011 in “Movement Disorders”

Finasteride reduces Tourette syndrome symptoms, but results may be limited due to potential biases.

research Finasteride-Associated Cataract And Intraoperative Floppy-Iris Syndrome

29 citations , May 2011 in “Journal of Cataract and Refractive Surgery”

Finasteride may cause cataracts and floppy-iris syndrome.

research Persistent Sexual Side Effects of Finasteride for Male Pattern Hair Loss

185 citations , March 2011 in “The Journal of Sexual Medicine”

Finasteride for hair loss can cause long-lasting sexual side effects like low libido and erectile dysfunction.

research Steroid 5α-Reductase as a Novel Therapeutic Target for Schizophrenia and Other Neuropsychiatric Disorders

72 citations , January 2011 in “Current Pharmaceutical Design”

S5αR inhibitors might help treat schizophrenia and other mental disorders but need more research.

Adverse Side Effects of 5α-Reductase Inhibitors Therapy: Persistent Diminished Libido, Erectile Dysfunction, and Depression in a Subset of Patients

research Adverse Side Effects of 5α-Reductase Inhibitors Therapy: Persistent Diminished Libido, Erectile Dysfunction, and Depression in a Subset of Patients

223 citations , December 2010 in “The Journal of Sexual Medicine”

Some patients taking finasteride or dutasteride may have ongoing sexual problems and depression even after stopping the medication.

research Efficacy and Safety of Finasteride Therapy for Androgenetic Alopecia

152 citations , October 2010 in “Archives of Dermatology”

Finasteride helps hair growth but may cause sexual side effects.

research SRD5A3 Is Required for Converting Polyprenol to Dolichol and Is Mutated in a Congenital Glycosylation Disorder

260 citations , July 2010 in “Cell”

Mutations in the SRD5A3 gene cause a new type of glycosylation disorder by blocking the production of a molecule necessary for protein glycosylation.

research Finasteride Treatment Inhibits Adult Hippocampal Neurogenesis in Male Mice

32 citations , May 2010 in “Pharmacopsychiatry”

Finasteride reduces new brain cells in male mice, possibly causing depression.

research An Overview on 5α-Reductase Inhibitors

219 citations , October 2009 in “Steroids”

5α-reductase inhibitors, like Finasteride and Dutasteride, help manage benign prostatic hyperplasia.

research Three Considerations Before Advising 5-Alpha-Reductase Inhibitors for Chemoprevention

6 citations , June 2009 in “Journal of Clinical Oncology”

5-α-reductase inhibitors don't prevent prostate cancer but may reduce unnecessary biopsies.

research Finasteride Treatment and Neuroactive Steroid Formation

9 citations , January 2009 in “PubMed”

Finasteride treatment can decrease certain steroids and increase others, possibly leading to depression symptoms in some cases.

research The Effect of 5-Reductase Inhibitors on Erectile Function

31 citations , September 2008 in “International Journal of Andrology”

5-alpha-reductase inhibitors may cause a low incidence of erectile dysfunction that decreases over time.

research Antipsychotic-Like Properties of 5-Alpha-Reductase Inhibitors

64 citations , March 2008 in “Neuropsychopharmacology”

research Finasteride 5mg and Sexual Side Effects: How Many Are Related to a Nocebo Phenomenon?

225 citations , July 2007 in “The Journal of Sexual Medicine”

Knowing about finasteride's sexual side effects increases reported dysfunction.

research Inhibition of Neurosteroid Synthesis Increases Asphyxia-Induced Brain Injury in the Late Gestation Fetal Sheep

100 citations , April 2007 in “Neuroscience”

Reducing neurosteroid levels worsens brain injury in fetal sheep.

research Finasteride Induced Depression: A Prospective Study

99 citations , October 2006 in “BMC clinical pharmacology”

Finasteride may cause slight depression and anxiety.

research Neurosteroids, Neuroactive Steroids, and Symptoms of Affective Disorders

82 citations , August 2006 in “Pharmacology, Biochemistry and Behavior”

Certain steroids in the brain affect mood and symptoms of depression, and treatments targeting these steroids show promise for improving these symptoms.

research The Long-Term Effect of Doxazosin, Finasteride, and Combination Therapy on the Clinical Progression of Benign Prostatic Hyperplasia

1707 citations , December 2003 in “The New England Journal of Medicine”

Combination therapy of doxazosin and finasteride safely and effectively reduces benign prostatic hyperplasia progression risk.

research Depression Related to Finasteride Administration for Androgenetic Alopecia

88 citations , October 2002 in “Journal of Dermatology”

Finasteride for hair loss may cause depression, affecting sleep and relationships.

research Steroid 5α-Reductases and 3α-Hydroxysteroid Dehydrogenases: Key Enzymes in Androgen Metabolism

115 citations , March 2001 in “Baillière's best practice and research in clinical endocrinology and metabolism/Baillière's best practice & research. Clinical endocrinology & metabolism”

Key enzymes control androgen levels, affecting hormone activity and potential treatments.

research Comparison of Spironolactone, Flutamide, and Finasteride Efficacy in the Treatment of Hirsutism: A Randomized, Double-Blind, Placebo-Controlled Trial

46 citations , January 2000 in “The Journal of Clinical Endocrinology and Metabolism”

Comparison of Spironolactone, Flutamide, and Finasteride Efficacy in the Treatment of Hirsutism: A Randomized, Double-Blind, Placebo-Controlled Trial

research Comparison of Spironolactone, Flutamide, and Finasteride Efficacy in the Treatment of Hirsutism: A Randomized, Double-Blind, Placebo-Controlled Trial

94 citations , January 2000 in “The Journal of Clinical Endocrinology and Metabolism”

Spironolactone most effective for hirsutism, but has side effects.

research Finasteride in the Treatment of Men with Androgenetic Alopecia

581 citations , October 1998 in “Journal of The American Academy of Dermatology”

Finasteride safely and effectively treats male pattern hair loss, but may cause reversible sexual issues and harm male fetuses.

The Effect of Finasteride on the Risk of Acute Urinary Retention and the Need for Surgical Treatment Among Men with Benign Prostatic Hyperplasia

research The Effect of Finasteride on the Risk of Acute Urinary Retention and the Need for Surgical Treatment Among Men with Benign Prostatic Hyperplasia

1054 citations , February 1998 in “The New England Journal of Medicine”

Finasteride reduces urinary issues and surgery need in men with enlarged prostates by over 50%.

Outcome of Long-Term Treatment with the 5α-Reductase Inhibitor Finasteride in Idiopathic Hirsutism: Clinical and Hormonal Effects During a 1-Year Course of Therapy and 1-Year Follow-Up

research Outcome of Long-Term Treatment with the 5α-Reductase Inhibitor Finasteride in Idiopathic Hirsutism: Clinical and Hormonal Effects During a 1-Year Course of Therapy and 1-Year Follow-Up

75 citations , November 1996 in “Fertility and Sterility”

Finasteride effectively reduces hair growth in women with idiopathic hirsutism, but requires careful contraception during treatment.

Mechanism-Based Inhibition of Human Steroid 5α-Reductase by Finasteride: Enzyme-Catalyzed Formation of NADP-Dihydrofinasteride, a Potent Bisubstrate Analog Inhibitor

research Mechanism-Based Inhibition of Human Steroid 5α-Reductase by Finasteride: Enzyme-Catalyzed Formation of NADP-Dihydrofinasteride, a Potent Bisubstrate Analog Inhibitor

136 citations , March 1996 in “Journal of the American Chemical Society”

Finasteride effectively blocks enzyme causing male pattern baldness.

research Clinical and Hormonal Effects of the 5 Alpha-Reductase Inhibitor Finasteride in Idiopathic Hirsutism

33 citations , October 1994 in “The Journal of Clinical Endocrinology and Metabolism”

Finasteride reduces hair growth and is safe for women with excessive hair.

research The Clinical Development of a 5α-Reductase Inhibitor, Finasteride

211 citations , November 1990 in “The Journal of Steroid Biochemistry and Molecular Biology”

Finasteride effectively treats BPH, but needs more trials to understand potential.