Finasteride significantly reduced sperm production and caused testicular atrophy in hamsters.
July 2007 in “Journal of Reproduction & Infertility” Short-term finasteride use likely doesn't harm male fertility.
Long-term finasteride use may affect sperm structure and chromosomes.
Spironolactone does not change hair growth.
December 2004 in “Differentiation” 
Spironolactone with an oral contraceptive improved hair growth in women with hirsutism.
January 2003 in “Zhongguo linchuang jiepouxue zazhi” Human hair keratin may help repair injured spinal cord tissue in rats.
The 2% spironolactone cream did not reduce hair growth in women with facial hirsutism.
January 2001 in “Zhongguo linchuang jiepouxue zazhi” Human hair keratin may help repair spinal cord injuries.
January 1994 in “Journal of Dermatological Treatment” Spironolactone helped reduce excessive facial hair in a woman with porphyria cutanea tarda.
January 1989 in “Oxford University Research Archive (ORA) (University of Oxford)” Spironolactone effectively reduces unwanted hair growth in women with hirsutism.
October 1988 in “Pediatric research” Certain maturity signs appear before and after the first release of sperm in boys.
Spironolactone was effective in reducing hair growth in women with hirsutism.
October 1986 in “Inpharma” Spironolactone helps reduce hair growth in women with hirsutism but may cause menstrual irregularities.
A man had temporary hair loss after a spinal cord injury, with some permanent thinning remaining.
January 1984 in “Isotopenpraxis Isotopes in Environmental and Health Studies” Trace element levels in hair differ in people with thyroid diseases.
November 1982 in “Inpharma” Spironolactone reduces hair growth in women with unexplained excessive hairiness.
January 1980 in “AFA Watchbird” Spectral-analysis can help diagnose mineral imbalances in birds.
April 2023 in “International Journal of Women's Dermatology” Spironolactone is safe for breast cancer survivors with alopecia and does not increase cancer risk.
April 2023 in “Journal of Investigative Dermatology” TGFβ-2 may cause hair loss in androgenetic alopecia.
April 2023 in “Journal of Investigative Dermatology” Low-dose spironolactone effectively treats female pattern hair loss with mild side effects.
April 2023 in “Australasian Journal of Dermatology” Both methods of platelet-rich plasma showed positive effects on hair loss.
March 2023 in “Current Pharmaceutical Design” Spironolactone is effective for idiopathic hirsutism but has limited effects on other PCOS symptoms.
March 2023 in “Clinical, Cosmetic and Investigational Dermatology” Spironolactone can effectively treat hair loss with manageable side effects.
November 2022 in “Al-Azhar International Medical Journal (Print)” Combining 5% spironolactone and 5% minoxidil is safe and more effective for treating hair loss.
September 2022 in “Journal of The American Academy of Dermatology” Monitoring potassium levels is important for women taking spironolactone.
September 2022 in “Journal of The American Academy of Dermatology” Dermatologists should monitor potassium levels in women taking spironolactone for acne, hair loss, and hirsutism.
September 2022 in “Journal of The American Academy of Dermatology” Older women taking spironolactone for hair loss may need yearly potassium checks due to a higher risk of hyperkalemia.
January 2022 in “Journal of Cosmetic Dermatology” Placebo effects vary in hair loss trials, with split-scalp trials showing higher hair density after 6 months compared to whole-head trials.
April 2021 in “Journal of Investigative Dermatology” Spironolactone safely and effectively treats hair loss in female scarring alopecia patients.