Topic
Antiandrogen comparison for hair loss
A side-by-side of the drugs, topicals and supplements that work on the androgen pathway, with who they were studied in and how strong the evidence is.
Key takeaways
- Men: finasteride is the best-evidenced drug (large trials). Dutasteride lowers DHT more and beat finasteride 1 mg in head-to-head trials, but outside Korea and Japan it is off-label. Kaufman 1998; Gubelin Harcha 2014 See finasteride and dutasteride.
- Women: finasteride 1 mg failed in postmenopausal women in a 1-year trial. Spironolactone is the most-used oral option, with trial support mainly as an add-on to minoxidil. Price 2000; Werachattawatchai 2025 See spironolactone.
- Bicalutamide is a second-line option in women, and 2026 comparisons with spironolactone disagree: hair counts favoured bicalutamide, while a 24-month clinical-rating cohort favoured spironolactone. Jha 2026; Gil-Redondo 2026
- Flutamide and cyproterone acetate have older, small, mixed trials and serious safety flags (liver failure; meningioma). Carmina 2003; Weill 2021
- Topical antiandrogens are the 2026 story. Clascoterone 5% reported positive phase 3 results in 1,465 men (company data, filing planned early 2027); pyrilutamide reported a positive China pivotal result; GT20029 is earlier. A topical finasteride spray is already authorised in parts of the EU.
- Supplements such as saw palmetto and pumpkin seed oil have small, short, mostly industry-linked trials. "5-alpha-reductase blocker" claims for beta-sitosterol or spearmint are not backed by hair data. Evron 2020
- A Delphi consensus of 11 Canadian physicians recommended oral and topical finasteride, oral dutasteride, topical and oral minoxidil, PRP and microneedling, and listed flutamide as not recommended. Landells 2025
The three ways in
Pattern hair loss depends on testosterone being converted to DHT and on DHT acting on the follicle's androgen receptor. There are three ways in:
- Block the enzyme that makes DHT: finasteride, dutasteride, and weakly some botanicals.
- Block the receptor: spironolactone, bicalutamide, flutamide, cyproterone, clascoterone, pyrilutamide and RU58841.
- Destroy the receptor: GT20029.
The biology is in DHT and pattern hair loss.
Comparison table
| Option | Route | Studied in | Best evidence | Approved for hair? | Main safety flag |
|---|---|---|---|---|---|
| Finasteride | oral 1 mg; topical spray exists | men (no benefit in a postmenopausal-women trial) | About 107 to 138 more hairs than placebo in a vertex circle at 1 to 2 years Kaufman 1998 | Yes, men (US, EU, UK) | Sexual and mood reports, EU/UK warnings, debated persistent symptoms; harms a male fetus |
| Dutasteride | oral 0.5 mg; mesotherapy | men | 0.5 mg beat finasteride 1 mg in 917 men Gubelin Harcha 2014 | Korea and Japan only | Same warnings as finasteride, longer half-life |
| Spironolactone | oral | women | Small trials as add-on to minoxidil, large case series | No (off-label) | High potassium, irregular periods, pregnancy; not for men |
| Bicalutamide | oral 50 mg | women | One 204-woman trial, retrospective cohorts | No | Liver injury, pregnancy |
| Flutamide | oral or topical | women | One small unmasked trial | No | Boxed warning: liver failure |
| Cyproterone acetate | oral | women | Two trials, mixed | No | Dose-related meningioma; EMA restrictions |
| Oral contraceptives | oral | women | Indirect, mostly acne and excess hair | No | Clots; meningioma with some progestogens |
| Clascoterone | topical 5% | men | Two phase 3 trials, company-reported | No (1% acne cream approved in the US) | Reported similar to vehicle |
| Pyrilutamide | topical | men | Company-reported China pivotal trial | No | Reported mild |
| GT20029 | topical | men | 12-week phase 2 in 180 men | No | Reported mild |
| Alfatradiol | topical | women | Slowed loss only, in one trial | Germany | Low |
| RU58841 | topical | none (animal) | Graft and macaque data; human absorption shown in 2026 | No (research chemical) | Unknown |
| Fluridil | topical | men | One 43-man inventor study | Cosmetic in some markets | Unknown |
| Saw palmetto | oral or topical | both | Small trials; 38% vs 68% improved in an open comparison with finasteride Rossi 2012 | No (supplement) | Low |
| Pumpkin seed oil | oral or topical | both | Two small trials | No | Low |
| Beta-sitosterol, spearmint | oral | none for hair | Lab and hormone data only | No | Low |
| Creatine | oral | men | One trial: no change in DHT or hair | n/a | n/a |
Pipeline
- A long-acting finasteride injection (IVL3001) has a 40-person pharmacokinetic study registered, and a topical minoxidil-finasteride foam (CG2001) has a 44-person phase 1 published in 2026. Li 2026; NCT04945226
- The dutasteride injection CKD-843 (every 3 months) is in a 288-man Korean phase 3. NCT06916793
What it means for your hair
- Men with early recession or crown thinning: the strongest evidence is for oral and topical finasteride and dutasteride. The EU product information says efficacy at the temples is not established, so keep expectations realistic.
- Women who could become pregnant: any oral antiandrogen needs reliable contraception, and the choice differs by whether signs of hormone excess (acne, excess hair, irregular periods) are present. Ong 2025
- Postmenopausal women: finasteride 1 mg did not help in a placebo-controlled trial, though higher-dose open studies exist; spironolactone and topicals are used. Price 2000
- Coarse or tightly coiled hair and traction or scarring alopecia: pattern-loss data come mostly from lighter-skinned groups, and androgen-pathway drugs do not treat scarring or traction alopecia, so get a diagnosis first.
Myths and facts
- Myth: you need high hormone levels to have pattern hair loss. Fact: in an 80-woman antiandrogen series no hormone level predicted who responded, and the follicle's own sensitivity and genetics matter. Sinclair 2005
- Myth: natural DHT blockers equal finasteride. Fact: in the head-to-head open study, saw palmetto helped 38% vs 68% on finasteride. Rossi 2012
- Myth: topical antiandrogens will replace pills now. Fact: none of the new topical agents is approved for hair as of 10 October 2026, and filings are planned for 2027 or later.
Bottom line
Match the option to sex, pregnancy plans and hormone signs, and leave prescription antiandrogens to a clinician. Most patterns also benefit from minoxidil, which works by a different pathway (see minoxidil). Judge response at 6 to 12 months using the same photos, because most studies above ran only 12 to 24 weeks. Discuss with a doctor.
Studies 16
Kaufman KD et al. Finasteride in the treatment of men with androgenetic alopecia. J Am Acad Dermatol. 1998
Tested: finasteride 1 mg/day vs placebo
Result: Finasteride grew about 107 more hairs than placebo at 1 year and about 138 more at 2 years in a 5.1 cm2 vertex circle (baseline about 876); placebo men kept losing hair.
Read the study ↗Gubelin Harcha W et al. 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. J Am Acad Dermatol. 2014
Tested: dutasteride 0.02, 0.1 or 0.5 mg vs finasteride 1 mg vs placebo
Result: Dutasteride 0.5 mg beat finasteride 1 mg on hair count, hair width and frontal photos; adverse events were similar. GSK-funded.
Read the study ↗Price VH et al. Lack of efficacy of finasteride in postmenopausal women with androgenetic alopecia. J Am Acad Dermatol. 2000
Tested: finasteride 1 mg/day vs placebo
Result: No benefit over placebo on any endpoint.
Read the study ↗Werachattawatchai P et al. Oral spironolactone for female pattern hair loss in premenopausal women: placebo-controlled pilot randomized controlled trial. Int J Womens Dermatol. 2025
Tested: spironolactone 100 mg vs placebo
Result: Moderate-to-marked improvement in 38% vs 9% (p = 0.034); terminal hairs +9.5 vs +5.3/cm2 (p = 0.063); menstrual irregularity 37.5%.
Read the study ↗Jha AK et al. Spironolactone vs bicalutamide in female pattern hair loss: randomized clinical trial. Clin Exp Dermatol. 2026
Tested: bicalutamide 50 mg vs spironolactone 100 mg
Result: Frontal hair count rose 5.05 vs 3.13/cm2 favouring bicalutamide (p<0.001); vertex 6.32 vs 3.06; the authors found no significant difference in clinical endpoints; adverse events 11.7% vs 18.6%.
Read the study ↗Gil-Redondo R et al. Spironolactone versus bicalutamide for female pattern hair loss: 24-month retrospective study. Dermatol Ther (Heidelb). 2026
Tested: spironolactone (128) vs bicalutamide (59)
Result: At least one grade of improvement in 54.4% on spironolactone vs 37.3% on bicalutamide (p = 0.030); more laboratory abnormalities with bicalutamide; spironolactone doses above 100 mg did best.
Read the study ↗Show 10 more studies
Carmina E, Lobo RA. Treatment of hyperandrogenic alopecia in women. Fertil Steril. 2003
Tested: flutamide 250 mg, cyproterone acetate 50 mg plus ethinyl estradiol, finasteride 5 mg, or no treatment
Result: Only flutamide moved the Ludwig score (21% reduction); the other treatments were not significant.
Read the study ↗Weill A et al. High dose cyproterone acetate and intracranial meningioma: a cohort study of 253,777 women in France. BMJ. 2021
Tested: cyproterone acetate
Result: Adjusted hazard ratio 6.6 (95% CI 4.0-11.1) for meningioma surgery or radiotherapy, 21.7 above 60 g cumulative dose.
Read the study ↗Evron E et al. Saw palmetto, a systematic review in alopecia. Skin Appendage Disord. 2020
Tested: saw palmetto-containing products, 100-320 mg
Result: Positive effects reported (for example density up in 83% of patients in one study); the authors say high-quality data are lacking and many products were blends.
Read the study ↗Rossi A et al. Finasteride 1 mg daily administration vs Serenoa repens 320 mg in male androgenetic alopecia: two-year study. Int J Immunopathol Pharmacol. 2012
Tested: Serenoa repens 320 mg/day vs finasteride 1 mg/day
Result: Hair growth increased in 38% on saw palmetto vs 68% on finasteride.
Read the study ↗Landells I et al. A Canadian consensus on androgenetic alopecia. J Cutan Med Surg. 2025
Tested: expert ratings of 17+ interventions
Result: Recommended oral and topical finasteride, oral dutasteride, minoxidil, PRP and microneedling; listed flutamide among interventions not recommended.
Read the study ↗Sinclair R et al. Treatment of female pattern hair loss with oral antiandrogens. Br J Dermatol. 2005
Tested: spironolactone 200 mg or cyproterone acetate (open, no placebo)
Result: 44% regrew, 44% stayed stable and 12% kept losing hair; results were similar for both drugs and no hormone level predicted response.
Read the study ↗Ong MM et al. Antiandrogen therapy for female pattern hair loss: clinical review. 2025
Tested: review of antiandrogen options
Result: Choice of antiandrogen differs by whether hormone excess (acne, hirsutism, irregular periods) is present.
Read the study ↗Li Y et al. CG2001 (topical minoxidil-finasteride foam): phase 1. 2026
Tested: topical minoxidil-finasteride foam
Result: Phase 1 study published in 2026.
Read the study ↗Inventage Lab. IVL3001 (long-acting finasteride injection) pharmacokinetic study. ClinicalTrials.gov NCT04945226
Tested: long-acting finasteride injection
Result: Registered pharmacokinetic study.
Read the study ↗Chong Kun Dang. Phase 3 study of CKD-843 in male androgenetic alopecia. ClinicalTrials.gov NCT06916793
Tested: CKD-843 injection every 3 months vs oral dutasteride vs placebo
Result: Registered phase 3; primary completion expected September 2027.
Read the study ↗Related
- FinasterideA prescription pill (and in some countries a scalp spray) that lowers DHT and is the best-proven drug for stopping male pattern hair loss.
- DutasterideA stronger cousin of finasteride that blocks both forms of the DHT-making enzyme and grew more hair than finasteride in head-to-head trials.
- SpironolactoneA cheap blood-pressure pill that blocks androgen receptors and is the most widely used off-label hormonal treatment for women's pattern hair loss.
- BicalutamideA prostate-cancer drug that blocks the androgen receptor and is used off-label by some specialists for women's hair loss, with liver-monitoring and pregnancy rules.
- FlutamideAn older prostate-cancer antiandrogen that helped women's hair loss modestly in one small trial but carries a boxed warning for liver failure.
- Cyproterone acetateA steroid antiandrogen used in Europe for women's hair loss and excess hair, with mixed trial results and a dose-related risk of meningioma.
- Oral contraceptives and antiandrogenic progestinsSome birth-control pills lower androgens or block their receptor, but almost no trial shows that any pill regrows scalp hair.
- ClascoteroneA topical androgen blocker already approved as an acne cream whose 5% scalp solution reported positive phase 3 results in men; it is not yet approved for hair.
- PyrilutamideA topical androgen blocker from the Chinese company Kintor that reported positive pivotal results in China; no peer-reviewed efficacy paper yet.
- GT20029A topical drug that tags the androgen receptor for destruction instead of just blocking it; a 12-week phase 2 in Chinese men showed modest gains.
- AlfatradiolA weakly hormonal topical estradiol approved for pattern hair loss in Germany; in the one randomised comparison it only slowed loss while minoxidil grew hair.
- RU58841A topical androgen blocker from the 1990s that grew hair in animal and graft models but has no human efficacy trial and is sold online as a research chemical.
- FluridilA topical antiandrogen designed to break down in the skin; its only human evidence is one small 2002 trial by its inventors.
- Saw palmettoA berry extract with weak DHT-blocking activity that shows small benefits in short, mostly industry-linked trials and clearly less than finasteride in the one head-to-head.
- Pumpkin seed oilA food oil with two small randomised trials for pattern hair loss that look promising but are short, single-centre and unreplicated.
- Beta-sitosterolA plant sterol credited with weak anti-DHT activity, but no hair trial has tested it on its own.
- SpearmintSpearmint tea lowered free testosterone in two small trials of women with excess hair growth, but no study has tested it for scalp hair loss.
- CreatineThe idea that creatine causes baldness comes from one 2009 rugby study that never looked at hair; a 2025 randomised trial found no effect on DHT or hair.
- MinoxidilThe most widely used hair-growth treatment, available as a cheap over-the-counter lotion or foam and as a prescription tablet, with a mechanism that is still only partly understood.
- DHT and pattern hair lossPattern hair loss happens when genetically sensitive scalp follicles respond to the hormone DHT by shrinking a little more with every hair cycle.