Tools
5α-Reductase Inhibitors
Indications
5α-reductase inhibitors (5-ARIs), specifically finasteride and dutasteride, are medications approved by the U.S. Food and Drug Administration (FDA) for treating 2 conditions: benign prostatic hyperplasia (BPH) and androgenic alopecia (male pattern hair loss).[1][2]
FDA-Approved Indications
Benign Prostatic Hyperplasia
BPH is typically seen in older men, and its frequency increases with age. BPH correlates with lower urinary tract symptoms that can cause significant distress, including nocturia, urinary urgency, increased frequency of urination, decreased stream caliber, straining while voiding, intermittency, and a sensation of incomplete bladder emptying.[3]
The symptoms mentioned above can significantly affect the quality of life of patients with BPH and can cause severe disruptions in sleeping patterns. Several theories for the etiology of BPH exist. One widely accepted view involves the androgen dihydrotestosterone (DHT) binding to intracellular androgen receptors in the prostate, leading to increased transcription of proteins responsible for increased cellular proliferation.[3] DHT is a hormone that contributes to prostate growth and hair loss. As the gland enlarges, it can compress the prostatic urethra, producing the symptoms described above.
Both finasteride and dutasteride have proven effective for treating BPH. Finasteride reduces prostatic DHT by over 90% and serum DHT by up to 70%; these reductions were dosage-independent.[1][4] Furthermore, finasteride significantly reduces prostatic volume, which contributes to distressing urinary symptoms.[2][5][6] Similarly, dutasteride reduces DHT by up to 99% in both the prostate and the serum. These reductions in prostatic DHT levels significantly decrease serum prostate-specific antigen (PSA) levels by 50% and reduce prostate volume by approximately 25% over time.[3][7] The majority of PSA reduction occurs within the first 3 months of treatment, while prostate reduction typically takes about 6 months to achieve maximal effect. However, this may require up to a year.[1][7]
The 50% reduction in PSA levels must be considered when screening for prostate cancer in men who are taking 5-ARIs.[8] For instance, if a patient has been on 5-ARIs for 6 months or longer, his PSA level should be doubled for comparative and risk assessment purposes. All patients should be screened for prostate cancer before initiating treatment with 5-ARIs.[8]
BPH is clinically monitored using a symptom score, such as the one published by the American Urological Association (AUA). Symptom scores above 10 points usually indicate further therapy. Patients with smaller prostates display better responses to α-blocker medications. In contrast, patients with larger prostates tend to benefit more from 5-ARIs, although this response may take longer to manifest. In clinical practice, many patients with BPH are initially prescribed α-blockers for immediate symptom relief, with 5-ARIs added for larger prostates or when α-blockers become ineffective.[3][9]
Additionally, 5-ARIs are effective in reducing prostatic bleeding and are often administered to patients undergoing transurethral prostate surgery for this purpose.[1][10][11][12][13][14][15] Although the exact mechanism remains unclear, it is believed to involve a reduction in microvascular density.[12][13][14] The medication should be initiated at least 2 weeks before surgery to minimize operative and postoperative bleeding.[15]
Androgenic Alopecia
Androgenic alopecia, commonly known as male-pattern hair loss, affects millions of men and women globally, affecting approximately 50% of men and potentially an equal number of women aged 40 or older. Additionally, alopecia is reported in up to 13% of premenopausal women to some degree. This condition is associated with significant morbidity, as changes in physical appearance can profoundly affect the patient's well-being. Androgenic alopecia contributes to a substantial portion of these cases. Hair loss typically begins at the crown of the scalp and advances anteriorly, while the temporal and occipital portions of the head are often spared.[16] This effect is attributed to DHT, which promotes hair miniaturization by interacting with androgen-sensitive receptors.[16]
The follicular response to androgens varies depending on the body's location. For instance, in areas such as the face, androgens stimulate the growth of facial hair, producing anabolic effects. Conversely, the opposite effect occurs in regions such as the scalp's crown (or vertex), leading to diminished hair growth. While male pattern baldness is a natural phenomenon associated with aging, hair loss can evoke emotional distress, particularly among younger populations.
The 2 most common first-line FDA-approved treatments for male pattern hair loss are topical minoxidil and oral finasteride, with finasteride generally considered more effective.[17] Although these medications are effective, they are not cures, as any benefits gained from the treatment are typically lost after discontinuing them. Hair shedding and loss usually begin around 2 weeks after finasteride discontinuation, with all newly regrown hair being lost within a year.
Numerous studies have tested the efficacy of oral finasteride in treating androgenic alopecia, revealing a significant improvement in the condition. However, it may take up to 12 months to achieve maximal effect.
- A study found that while individuals receiving no treatment for androgenic alopecia experienced a 26% loss in hair count over 5 years, patients treated with finasteride showed a 10% increase within 12 months.[2][16][18][19][20][21]
- Another study provided evidence of finasteride's effectiveness in managing androgenic alopecia, with all patients demonstrating increased hair count after 12 months of treatment.[2][6][16][18][19][20][21]
Finasteride reduces hair loss in approximately 88% of men and aids in regrowing hair in about 66% of cases. Studies indicate that oral finasteride is more effective than topical minoxidil.[17] Additionally, combining oral finasteride with topical minoxidil yields superior results to either therapy alone.[22][23][24][22][24] The combination of topical finasteride and minoxidil has also shown greater efficacy than monotherapy, but it is not FDA-approved in the U.S.[23]
In a comparative study of treatment outcomes, the percentage of men who showed improvement in hair loss after a year of continuous therapy were:[24]
- Topical minoxidil (5%): 59%
- Finasteride oral 1 mg: 80.5%
- Combination topical minoxidil and oral finasteride: 94.1%
Off-Label Uses
Topical finasteride has shown comparable efficacy to the oral formulation but lacks FDA approval for this indication.[25][26][27] Conversely, oral minoxidil is FDA-approved in the United States for severe hypertension and is often prescribed off-label for hair loss treatment, where it demonstrates effectiveness.[28]
Dutasteride lacks FDA approval for treating hair loss but is commonly prescribed off-label for alopecia.[29] Comparative studies indicate that dutasteride is as effective as (and possibly superior to) finasteride in treating hair loss.[29][30][31][32] Only topical minoxidil and oral finasteride have been approved by the FDA for male hair loss treatment in the United States.[6][16][33][34]
The longer half-life of dutasteride makes it amenable for scalp microinjection therapy using 0.01% dutasteride solution.[21] Case studies suggest efficacy, but randomized controlled trials are lacking.[21][35][36]
5-ARIs have shown efficacy in enhancing overall survival and reducing the incidence of bladder cancer.[37][38][39][40] Additionally, existing evidence suggests that men with prostate cancer who take 5-ARIs experience a decreased risk of disease progression.[41]
Although not FDA-approved for idiopathic female hirsutism, clinicians have used 5-ARIs to manage this condition, with some success.[42]
Mechanism of Action
Register For Free And Read The Full Article
Search engine and full access to all medical articles- 10 free questions in your specialty
- Free CME/CE Activities
- Free daily question in your email
- Save favorite articles to your dashboard
- Emails offering discounts
Learn more about a Subscription to StatPearls Point-of-Care
Mechanism of Action
The gonads, and to a lesser extent, the adrenal glands, produce androgens through a process beginning with cholesterol. Once formed, testosterone binds to intracellular androgen receptors throughout the body to exert its effects. DHT binds to the androgen receptor in the cell's cytoplasm, initiating a pathway that alters nuclear gene expression.[43][44]
DHT, a more potent androgen, is formed from testosterone by the isoenzymes of 5α-reductase (types 1 and 2), primarily found in the scalp and prostate cells. While testosterone and DHT are androgenic steroids, they exert slightly different effects throughout the body. Testosterone is largely responsible for growth during puberty, increased muscle mass, and elevated hematocrit levels in males.[45] In contrast, DHT is crucial in the fetal differentiation of external male genitalia, male hair patterns, and prostatic growth.[43][45][46]
Finasteride and dutasteride are 5-ARIs designed to decrease the intracellular production of DHT.[47] Although these drugs are competitive inhibitors of 5α-reductase, finasteride selectively inhibits the type 2 isoenzyme, whereas dutasteride blocks both type 1 and 2 isoenzymes.[47] A significant clinical difference between these 2 medications does not exist.[47] The only clinically significant pharmacological difference is their half-life: 6 to 8 hours for finasteride and 4 to 5 weeks for dutasteride.[6][48][49]
These drugs are prescribed to reduce male pattern hair loss in androgenic alopecia as well as prostatic growth and size in BPH.[45] A recent meta-analysis demonstrated that oral 5-ARIs are more effective than minoxidil or newer treatment modalities like botulinum toxin, microneedling, and photobiomodulation for managing androgenetic alopecia.[50]
Administration
Available Dosage Forms and Strengths: Finasteride is available in 1 mg and 5 mg tablets. Dutasteride is available in 0.5 mg capsules.
Adult Dosage: The standard daily dosage of finasteride is 1 mg for androgenic alopecia and 5 mg for BPH. The standard dosage of dutasteride is 0.5 mg once daily.
Adverse Effects
The reported adverse effects of 5-ARIs are primarily sexual and include erectile dysfunction, reduced ejaculatory volume, decreased libido, and gynecomastia. These symptoms are believed to be caused by reduced DHT levels and the shunting of testosterone to estradiol.
Drug-Drug Interactions
Finasteride and dutasteride inhibit 5α-reductase, which converts testosterone to DHT, increasing serum testosterone levels. Excess testosterone is then converted into estradiol by aromatase, which can result in gynecomastia. Orthostatic hypotension has also been documented in patients taking 5-ARIs. As dutasteride is often taken with tamsulosin, an α-1 blocker, reports of orthostatic hypotension, dizziness, and weakness have been documented.[6]
In rare instances, adverse effects have persisted even after discontinuing treatment. This condition is known as post-finasteride syndrome, and ongoing research aims to deepen our understanding of this disorder. Additionally, 5-ARIs may be associated with reduced fertility. However, this effect is reversible upon cessation of treatment, and patients often maintain the ability to conceive while taking 5-ARIs.[51] Notably, α-blockers, frequently prescribed alongside 5-ARIs, can interfere with ejaculation.[52][53]
Post-finasteride syndrome encompasses a range of adverse effects linked to the discontinuation of finasteride or dutasteride. These adverse effects may persist and involve ongoing mental, neurological, physical, or sexual dysfunction. Almost all cases include sexual dysfunction, with reports also indicating increased anxiety, depression, and suicidal ideations among men who cease 5-ARI therapy. Currently, treatment for this disorder does not exist.[54][55][56][57][58]
Contraindications
5-ARIs cause reduced levels of DHT, a critical androgen in sexual development. Therefore, children and pregnant or intending-to-be-pregnant women should refrain from using these drugs.[59] Additionally, individuals with a known hypersensitivity reaction to these drugs should avoid their use.[6]
Monitoring
Guidelines for monitoring responses to 5-ARIs do not exist. However, PSA concentrations can be valuable in evaluating the treatment of BPH. As the prostate typically produces elevated PSA in patients with BPH, reductions in prostatic volume lead to decreased PSA concentrations. The efficacy of 5-ARIs can be evaluated by measuring PSA concentrations.[6][60]
Several controversial studies have emerged suggesting a potential association between finasteride use and prostate cancer. Notably, the Prostate Cancer Prevention Trial investigated the prevalence of prostate cancer in men 55 or older on finasteride therapy. While this trial reported a 25% reduction in prostate cancer prevalence, it also noted an increased incidence of high-grade prostate cancer.[61] As a result, the FDA issued a boxed warning for finasteride in response to these findings.[62] However, subsequent studies have contradicted this, reporting no actual increased risk of prostate cancer in patients taking finasteride or dutasteride.[63][64][65][66]
For patients who have been on these drugs for 6 months or longer, measured PSA levels should be doubled to account for the effect of 5-ARIs.[3][7]
Toxicity
Reports of toxicity related to 5-ARIs have not been documented.
Enhancing Healthcare Team Outcomes
The 5α-reductase inhibitors (finasteride and dutasteride) are effective treatments for both BPH and androgenic alopecia. Given the longer duration of symptom relief, patient education by nurses, pharmacists, and physicians is crucial to ensure adherence. Patients should be thoroughly informed about potential adverse effects and screened for prostate cancer before starting these medications.
References
Smith AB, Carson CC. Finasteride in the treatment of patients with benign prostatic hyperplasia: a review. Therapeutics and clinical risk management. 2009 Jun:5(3):535-45 [PubMed PMID: 19707263]
Shin JW, Chung EH, Kim MB, Kim TO, Kim WI, Huh CH. Evaluation of long-term efficacy of finasteride in Korean men with androgenetic alopecia using the basic and specific classification system. The Journal of dermatology. 2019 Feb:46(2):139-143. doi: 10.1111/1346-8138.14719. Epub 2018 Dec 7 [PubMed PMID: 30536893]
Ng M, Leslie SW, Baradhi KM. Benign Prostatic Hyperplasia. StatPearls. 2024 Jan:(): [PubMed PMID: 32644346]
Norman RW, Coakes KE, Wright AS, Rittmaster RS. Androgen metabolism in men receiving finasteride before prostatectomy. The Journal of urology. 1993 Nov:150(5 Pt 2):1736-9 [PubMed PMID: 7692110]
. Treatments for Benign Prostatic Hyperplasia. 2004 Aug 2:(): [PubMed PMID: 25879123]
Zito PM, Bistas KG, Patel P, Syed K. Finasteride. StatPearls. 2024 Jan:(): [PubMed PMID: 30020701]
Hernandez J, Gelfond J, Goros M, Liss MA, Liang Y, Ankerst D, Thompson IM Jr, Leach RJ. The effect of 3-month finasteride challenge on biomarkers for predicting cancer outcome on biopsy: Results of a randomized trial. PloS one. 2018:13(10):e0204823. doi: 10.1371/journal.pone.0204823. Epub 2018 Oct 9 [PubMed PMID: 30300367]
Level 1 (high-level) evidenceJain MA, Leslie SW, Sapra A. Prostate Cancer Screening. StatPearls. 2024 Jan:(): [PubMed PMID: 32310541]
Nachawati D, Patel JB. Alpha-Blockers. StatPearls. 2024 Jan:(): [PubMed PMID: 32310526]
Puchner PJ, Miller MI. The effects of finasteride on hematuria associated with benign prostatic hyperplasia: a preliminary report. The Journal of urology. 1995 Nov:154(5):1779-82 [PubMed PMID: 7563345]
Miller MI, Puchner PJ. Effects of finasteride on hematuria associated with benign prostatic hyperplasia: long-term follow-up. Urology. 1998 Feb:51(2):237-40 [PubMed PMID: 9495704]
Foley SJ, Soloman LZ, Wedderburn AW, Kashif KM, Summerton D, Basketter V, Holmes SA. A prospective study of the natural history of hematuria associated with benign prostatic hyperplasia and the effect of finasteride. The Journal of urology. 2000 Feb:163(2):496-8 [PubMed PMID: 10647664]
Donohue JF, Hayne D, Karnik U, Thomas DR, Foster MC. Randomized, placebo-controlled trial showing that finasteride reduces prostatic vascularity rapidly within 2 weeks. BJU international. 2005 Dec:96(9):1319-22 [PubMed PMID: 16287453]
Level 1 (high-level) evidenceMemis A, Ozden C, Ozdal OL, Guzel O, Han O, Seckin S. Effect of finasteride treatment on suburethral prostatic microvessel density in patients with hematuria related to benign prostate hyperplasia. Urologia internationalis. 2008:80(2):177-80. doi: 10.1159/000112610. Epub 2008 Mar 19 [PubMed PMID: 18362489]
Ozdal OL, Ozden C, Benli K, Gökkaya S, Bulut S, Memiş A. Effect of short-term finasteride therapy on peroperative bleeding in patients who were candidates for transurethral resection of the prostate (TUR-P): a randomized controlled study. Prostate cancer and prostatic diseases. 2005:8(3):215-8 [PubMed PMID: 15999118]
Level 1 (high-level) evidenceHo CH, Sood T, Zito PM. Androgenetic Alopecia. StatPearls. 2024 Jan:(): [PubMed PMID: 28613674]
Arca E, Açikgöz G, Taştan HB, Köse O, Kurumlu Z. An open, randomized, comparative study of oral finasteride and 5% topical minoxidil in male androgenetic alopecia. Dermatology (Basel, Switzerland). 2004:209(2):117-25 [PubMed PMID: 15316165]
Level 1 (high-level) evidenceSasaki GH. Review of Human Hair Follicle Biology: Dynamics of Niches and Stem Cell Regulation for Possible Therapeutic Hair Stimulation for Plastic Surgeons. Aesthetic plastic surgery. 2019 Feb:43(1):253-266. doi: 10.1007/s00266-018-1248-1. Epub 2018 Oct 15 [PubMed PMID: 30324295]
Feingold KR, Anawalt B, Blackman MR, Boyce A, Chrousos G, Corpas E, de Herder WW, Dhatariya K, Dungan K, Hofland J, Kalra S, Kaltsas G, Kapoor N, Koch C, Kopp P, Korbonits M, Kovacs CS, Kuohung W, Laferrère B, Levy M, McGee EA, McLachlan R, New M, Purnell J, Sahay R, Shah AS, Singer F, Sperling MA, Stratakis CA, Trence DL, Wilson DP, Asfour L, Cranwell W, Sinclair R. Male Androgenetic Alopecia. Endotext. 2000:(): [PubMed PMID: 25905192]
Stough DB, Rao NA, Kaufman KD, Mitchell C. Finasteride improves male pattern hair loss in a randomized study in identical twins. European journal of dermatology : EJD. 2002 Jan-Feb:12(1):32-7 [PubMed PMID: 11809593]
Level 1 (high-level) evidenceCourtney A, Triwongwarant D, Chim I, Eisman S, Sinclair R. Evaluating 5 alpha reductase inhibitors for the treatment of male androgenic alopecia. Expert opinion on pharmacotherapy. 2023 Sep-Dec:24(18):1919-1922. doi: 10.1080/14656566.2023.2280630. Epub 2024 Jan 5 [PubMed PMID: 37942878]
Level 3 (low-level) evidenceChen L, Zhang J, Wang L, Wang H, Chen B. The Efficacy and Safety of Finasteride Combined with Topical Minoxidil for Androgenetic Alopecia: A Systematic Review and Meta-analysis. Aesthetic plastic surgery. 2020 Jun:44(3):962-970. doi: 10.1007/s00266-020-01621-5. Epub 2020 Mar 12 [PubMed PMID: 32166351]
Level 1 (high-level) evidenceRossi A, Caro G. Efficacy of the association of topical minoxidil and topical finasteride compared to their use in monotherapy in men with androgenetic alopecia: A prospective, randomized, controlled, assessor blinded, 3-arm, pilot trial. Journal of cosmetic dermatology. 2024 Feb:23(2):502-509. doi: 10.1111/jocd.15953. Epub 2023 Oct 5 [PubMed PMID: 37798906]
Level 1 (high-level) evidenceHu R, Xu F, Sheng Y, Qi S, Han Y, Miao Y, Rui W, Yang Q. Combined treatment with oral finasteride and topical minoxidil in male androgenetic alopecia: a randomized and comparative study in Chinese patients. Dermatologic therapy. 2015 Sep-Oct:28(5):303-8. doi: 10.1111/dth.12246. Epub 2015 Jun 2 [PubMed PMID: 26031764]
Level 1 (high-level) evidenceAbeck F, Hansen I, Kött J, Schröder F, Garrahy E, Veneroso J, Rünger A, Torster L, Schneider SW, von Büren J. Patient-reported outcomes of topical finasteride/minoxidil treatment for male androgenetic alopecia: A retrospective study using telemedical data. Journal of cosmetic dermatology. 2024 May 7:():. doi: 10.1111/jocd.16360. Epub 2024 May 7 [PubMed PMID: 38713003]
Level 2 (mid-level) evidenceKeerti A, Madke B, Keerti A, Lopez MJC, Lirio FS. Topical Finasteride: A Comprehensive Review of Androgenetic Alopecia Management for Men and Women. Cureus. 2023 Sep:15(9):e44949. doi: 10.7759/cureus.44949. Epub 2023 Sep 9 [PubMed PMID: 37818522]
Piraccini BM, Blume-Peytavi U, Scarci F, Jansat JM, Falqués M, Otero R, Tamarit ML, Galván J, Tebbs V, Massana E, Topical Finasteride Study Group. Efficacy and safety of topical finasteride spray solution for male androgenetic alopecia: a phase III, randomized, controlled clinical trial. Journal of the European Academy of Dermatology and Venereology : JEADV. 2022 Feb:36(2):286-294. doi: 10.1111/jdv.17738. Epub 2021 Oct 25 [PubMed PMID: 34634163]
Level 1 (high-level) evidenceGupta AK, Talukder M, Shemer A. Efficacy and safety of low-dose oral minoxidil in the management of androgenetic alopecia. Expert opinion on pharmacotherapy. 2024 Feb:25(2):139-147. doi: 10.1080/14656566.2024.2314087. Epub 2024 Feb 6 [PubMed PMID: 38315101]
Level 3 (low-level) evidenceArif T, Dorjay K, Adil M, Sami M. Dutasteride in Androgenetic Alopecia: An Update. Current clinical pharmacology. 2017:12(1):31-35. doi: 10.2174/1574884712666170310111125. Epub [PubMed PMID: 28294070]
Dhurat R, Sharma A, Rudnicka L, Kroumpouzos G, Kassir M, Galadari H, Wollina U, Lotti T, Golubovic M, Binic I, Grabbe S, Goldust M. 5-Alpha reductase inhibitors in androgenetic alopecia: Shifting paradigms, current concepts, comparative efficacy, and safety. Dermatologic therapy. 2020 May:33(3):e13379. doi: 10.1111/dth.13379. Epub 2020 Apr 24 [PubMed PMID: 32279398]
Level 2 (mid-level) evidenceChoi S, Kwon SH, Sim WY, Lew BL. Long-term efficacy and safety of dutasteride 0.5 mg in Korean men with androgenetic alopecia: 5-year data demonstrating clinical improvement with sustained efficacy. The Journal of dermatology. 2024 May:51(5):684-690. doi: 10.1111/1346-8138.17138. Epub 2024 Feb 6 [PubMed PMID: 38321615]
Gupta AK, Talukder M, Williams G. Comparison of oral minoxidil, finasteride, and dutasteride for treating androgenetic alopecia. The Journal of dermatological treatment. 2022 Nov:33(7):2946-2962. doi: 10.1080/09546634.2022.2109567. Epub 2022 Aug 15 [PubMed PMID: 35920739]
Gupta AK, Talukder M, Williams G. Emerging and traditional 5-α reductase inhibitors and androgen receptor antagonists for male androgenetic alopecia. Expert opinion on emerging drugs. 2024 Apr 26:():1-11. doi: 10.1080/14728214.2024.2346590. Epub 2024 Apr 26 [PubMed PMID: 38666717]
Level 3 (low-level) evidencePatel P, Nessel TA, Kumar D D. Minoxidil. StatPearls. 2024 Jan:(): [PubMed PMID: 29494000]
Saceda-Corralo D, Moustafa F, Moreno-Arrones Ó, Jaén-Olasolo P, Vañó-Galván S, Camacho F. Mesotherapy With Dutasteride for Androgenetic Alopecia: A Retrospective Study in Real Clinical Practice. Journal of drugs in dermatology : JDD. 2022 Jul 1:21(7):742-747. doi: 10.36849/JDD.6610. Epub [PubMed PMID: 35816059]
Level 2 (mid-level) evidenceRodríguez-Cuadrado FJ, Pinto-Pulido EL, Fernández-Parrado M. Mesotherapy with dutasteride for androgenetic alopecia: a concise review of the literature. European journal of dermatology : EJD. 2023 Feb 1:33(1):72. doi: 10.1684/ejd.2023.4443. Epub [PubMed PMID: 37178048]
Wang Y, Song Y, Peng Y, Han S, Qin C, Du Y, Xu T. Effects of androgen suppression therapy on the incidence and prognosis of bladder cancer: An updated systematic review and meta-analysis. Urologic oncology. 2024 May 9:():. pii: S1078-1439(24)00431-9. doi: 10.1016/j.urolonc.2024.04.014. Epub 2024 May 9 [PubMed PMID: 38729866]
Level 1 (high-level) evidencePyun JH, Son NH, Ko YH, Kim SW, Kim H, Bae YJ. The Long-Term Impact of 5-alpha Reductase Inhibitors on the Development of Bladder Cancer and the Need for Radical Cystectomy: A Nationwide Observational Study. The world journal of men's health. 2024 Apr:42(2):460-466. doi: 10.5534/wjmh.230137. Epub 2024 Jan 2 [PubMed PMID: 38164032]
Level 2 (mid-level) evidenceAn MH, Kim MS, Kim C, Noh TI, Joo KJ, Lee DH, Yi KH, Kwak JW, Hwang TH, Park RW, Kang SH. Association of 5α-Reductase Inhibitor Prescription With Bladder Cancer Progression in Males in South Korea. JAMA network open. 2023 May 1:6(5):e2313667. doi: 10.1001/jamanetworkopen.2023.13667. Epub 2023 May 1 [PubMed PMID: 37191958]
Garg H, Wheeler KM, Dursun F, Cooper RE, Pruthi DK, Kaushik D, Thompson IM, Svatek RS, Liss MA. Impact of Finasteride on Survival in Bladder Cancer: A Retrospective Multi-institutional Database Analysis. Clinical genitourinary cancer. 2023 Apr:21(2):314.e1-314.e7. doi: 10.1016/j.clgc.2022.10.014. Epub 2022 Oct 29 [PubMed PMID: 36402643]
Level 2 (mid-level) evidenceMatsukawa A, Yanagisawa T, Bekku K, Parizi MK, Laukhtina E, Klemm J, Chiujdea S, Mori K, Kimura S, Miki J, Pradere B, Rivas JG, Gandaglia G, Kimura T, Kasivisvanathan V, Ploussard G, Cornford P, Shariat SF, Rajwa P. Nonsurgical Interventions to Prevent Disease Progression in Prostate Cancer Patients on Active Surveillance: A Systematic Review and Meta-analysis. European urology oncology. 2024 Jun:7(3):376-400. doi: 10.1016/j.euo.2023.10.010. Epub 2023 Oct 28 [PubMed PMID: 38277189]
Level 1 (high-level) evidenceMoghetti P, Castello R, Magnani CM, Tosi F, Negri C, Armanini D, Bellotti G, Muggeo M. Clinical and hormonal effects of the 5 alpha-reductase inhibitor finasteride in idiopathic hirsutism. The Journal of clinical endocrinology and metabolism. 1994 Oct:79(4):1115-21 [PubMed PMID: 7962284]
Kinter KJ, Amraei R, Anekar AA. Biochemistry, Dihydrotestosterone. StatPearls. 2024 Jan:(): [PubMed PMID: 32491566]
Marchetti PM, Barth JH. Clinical biochemistry of dihydrotestosterone. Annals of clinical biochemistry. 2013 Mar:50(Pt 2):95-107. doi: 10.1258/acb.2012.012159. Epub 2013 Feb 21 [PubMed PMID: 23431485]
Level 3 (low-level) evidenceNassar GN, Leslie SW. Physiology, Testosterone. StatPearls. 2024 Jan:(): [PubMed PMID: 30252384]
Basaria S. Reproductive aging in men. Endocrinology and metabolism clinics of North America. 2013 Jun:42(2):255-70. doi: 10.1016/j.ecl.2013.02.012. Epub 2013 Apr 6 [PubMed PMID: 23702400]
Level 3 (low-level) evidenceNickel JC. Comparison of clinical trials with finasteride and dutasteride. Reviews in urology. 2004:6 Suppl 9(Suppl 9):S31-9 [PubMed PMID: 16985923]
Erdemir F, Harbin A, Hellstrom WJ. 5-alpha reductase inhibitors and erectile dysfunction: the connection. The journal of sexual medicine. 2008 Dec:5(12):2917-24. doi: 10.1111/j.1743-6109.2008.01001.x. Epub [PubMed PMID: 19090946]
Gisleskog PO, Hermann D, Hammarlund-Udenaes M, Karlsson MO. The pharmacokinetic modelling of GI198745 (dutasteride), a compound with parallel linear and nonlinear elimination. British journal of clinical pharmacology. 1999 Jan:47(1):53-8 [PubMed PMID: 10073740]
Level 1 (high-level) evidenceGupta AK, Bamimore MA, Wang T, Talukder M. The impact of monotherapies for male androgenetic alopecia: A network meta-analysis study. Journal of cosmetic dermatology. 2024 May 9:():. doi: 10.1111/jocd.16362. Epub 2024 May 9 [PubMed PMID: 38725143]
Level 1 (high-level) evidenceAndrade C. Why Odds Ratios Can Be Tricky Statistics: The Case of Finasteride, Dutasteride, and Sexual Dysfunction. The Journal of clinical psychiatry. 2018 Nov 27:79(6):. pii: 18f12641. doi: 10.4088/JCP.18f12641. Epub 2018 Nov 27 [PubMed PMID: 30549493]
Level 3 (low-level) evidenceBearelly P, Avellino GJ. The role of benign prostatic hyperplasia treatments in ejaculatory dysfunction. Fertility and sterility. 2021 Sep:116(3):611-617. doi: 10.1016/j.fertnstert.2021.07.1199. Epub [PubMed PMID: 34462095]
Bapir R, Bhatti KH, Eliwa A, García-Perdomo HA, Gherabi N, Hennessey D, Magri V, Mourmouris P, Ouattara A, Perletti G, Philipraj J, Trinchieri A, Buchholz N. Effect of alpha-adrenoceptor antagonists on sexual function. A systematic review and meta-analysis. Archivio italiano di urologia, andrologia : organo ufficiale [di] Societa italiana di ecografia urologica e nefrologica. 2022 Jun 30:94(2):252-263. doi: 10.4081/aiua.2022.2.252. Epub 2022 Jun 30 [PubMed PMID: 35775356]
Level 1 (high-level) evidenceTraish AM. Post-finasteride syndrome: a surmountable challenge for clinicians. Fertility and sterility. 2020 Jan:113(1):21-50. doi: 10.1016/j.fertnstert.2019.11.030. Epub [PubMed PMID: 32033719]
Coskuner ER, Ozkan B, Culha MG. Sexual Problems of Men With Androgenic Alopecia Treated With 5-Alpha Reductase Inhibitors. Sexual medicine reviews. 2019 Apr:7(2):277-282. doi: 10.1016/j.sxmr.2018.07.003. Epub 2018 Oct 6 [PubMed PMID: 30301703]
Said MA, Mehta A. The Impact of 5α-Reductase Inhibitor Use for Male Pattern Hair Loss on Men's Health. Current urology reports. 2018 Jun 16:19(8):65. doi: 10.1007/s11934-018-0814-z. Epub 2018 Jun 16 [PubMed PMID: 29909472]
Fertig RM, Gamret AC, Darwin E, Gaudi S. Sexual side effects of 5-α-reductase inhibitors finasteride and dutasteride: A comprehensive review. Dermatology online journal. 2017 Nov 11:23(11):. pii: 13030/qt24k8q743. Epub 2017 Nov 11 [PubMed PMID: 29447628]
Lee S, Lee YB, Choe SJ, Lee WS. Adverse Sexual Effects of Treatment with Finasteride or Dutasteride for Male Androgenetic Alopecia: A Systematic Review and Meta-analysis. Acta dermato-venereologica. 2019 Jan 1:99(1):12-17. doi: 10.2340/00015555-3035. Epub [PubMed PMID: 30206635]
Level 1 (high-level) evidenceTeichert M, van Puijenbroek E, Stricker BH. Contraindicated use of 5-alpha-reductase inhibitors in women. British journal of clinical pharmacology. 2017 Feb:83(2):429-431. doi: 10.1111/bcp.13118. Epub 2016 Sep 30 [PubMed PMID: 27567019]
Andy G, John M, Mirna S, Rachita D, Michael K, Maja K, Aseem S, Zeljana B. Controversies in the treatment of androgenetic alopecia: The history of finasteride. Dermatologic therapy. 2019 Mar:32(2):e12647. doi: 10.1111/dth.12647. Epub 2018 Sep 25 [PubMed PMID: 30253001]
Goodman PJ, Tangen CM, Darke AK, Lucia MS, Ford LG, Minasian LM, Parnes HL, LeBlanc ML, Thompson IM Jr. Long-Term Effects of Finasteride on Prostate Cancer Mortality. The New England journal of medicine. 2019 Jan 24:380(4):393-394. doi: 10.1056/NEJMc1809961. Epub [PubMed PMID: 30673548]
Shin YS, Karna KK, Choi BR, Park JK. Finasteride and Erectile Dysfunction in Patients with Benign Prostatic Hyperplasia or Male Androgenetic Alopecia. The world journal of men's health. 2019 May:37(2):157-165. doi: 10.5534/wjmh.180029. Epub 2018 Aug 10 [PubMed PMID: 30209896]
Hirshburg JM, Kelsey PA, Therrien CA, Gavino AC, Reichenberg JS. Adverse Effects and Safety of 5-alpha Reductase Inhibitors (Finasteride, Dutasteride): A Systematic Review. The Journal of clinical and aesthetic dermatology. 2016 Jul:9(7):56-62 [PubMed PMID: 27672412]
Level 1 (high-level) evidenceBonde Miranda T, Garmo H, Stattin P, Robinson D. 5α-Reductase Inhibitors and Risk of Prostate Cancer Death. The Journal of urology. 2020 Oct:204(4):714-719. doi: 10.1097/JU.0000000000001038. Epub 2020 Apr 3 [PubMed PMID: 32243243]
Vaselkiv JB, Ceraolo C, Wilson KM, Pernar CH, Rencsok EM, Stopsack KH, Grob ST, Plym A, Giovannucci EL, Olumi AF, Kibel AS, Preston MA, Mucci LA. 5-Alpha Reductase Inhibitors and Prostate Cancer Mortality among Men with Regular Access to Screening and Health Care. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2022 Jul 1:31(7):1460-1465. doi: 10.1158/1055-9965.EPI-21-1234. Epub [PubMed PMID: 35255119]
Unger JM, Till C, Thompson IM Jr, Tangen CM, Goodman PJ, Wright JD, Barlow WE, Ramsey SD, Minasian LM, Hershman DL. Long-term Consequences of Finasteride vs Placebo in the Prostate Cancer Prevention Trial. Journal of the National Cancer Institute. 2016 Dec:108(12):. pii: djw168. doi: 10.1093/jnci/djw168. Epub 2016 Aug 26 [PubMed PMID: 27565902]