Do 5α-Reductase Inhibitors Raise Circulating Serum Testosterone Levels? A Comprehensive Review and Meta-Analysis Explaining Paradoxical Results

August 2018 in “ Sexual Medicine Reviews ”

Abdulmaged M. Traish, Yonah Krakowsky, Gheorghe Doros, Abraham Morgentaler

5α-reductase inhibitors finasteride dutasteride serum testosterone luteinizing hormone follicle-stimulating hormone sex hormone-binding globulin estradiol 5α-RIs Propecia Avodart testosterone LH FSH SHBG estrogen

From the encyclopedia

Finasteride →

Frontline, gold standard treatment for combatting androgenic alopecia

Dutasteride →

Heavy duty finasteride that comes with higher risks

Estradiol →

an estrogen promoting hair regrowth more commonly used in women

Studysummary In this review and meta-analysis, the authors concluded that 5α-reductase inhibitor therapy is not consistently associated with significant increases in serum testosterone levels in men.

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23 / 23 results

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This study found that male 5αR1 knockout mice and obese Zucker rats treated with finasteride showed increased insulin resistance and hepatic steatosis, potentially implicating 5α-reductase activity in metabolic liver disease development.

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