Finasteride: The First 5α‐Reductase Inhibitor

@article{Sudduth1993FinasterideTF,
  title={Finasteride: The First 5$\alpha$‐Reductase Inhibitor},
  author={S L Sudduth and Michael J. Koronkowski},
  journal={Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy},
  year={1993},
  volume={13}
}
Finasteride is a synthetic 4‐azasteroid that is a specific competitive inhibitor of 5α‐reductase, an intracellular enzyme that converts testosterone to dihydrotestosterone (DHT). It has no binding affinity for androgen receptor sites and itself possesses no androgenic, antiandrogenic, or other steroid hormone‐related properties. It is well absorbed after oral administration, with absolute bioavailability in humans of 63% (range 34–108%). The mean time to maximum concentration is 1–2 hours, and… 
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TLDR
It is concluded that MK‐906 is a highly effective 5α‐reductase inhibitor in vivo, and both hepatic and extrasplanchnic 5α-reductases are inhibited.
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TLDR
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TLDR
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TLDR
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TLDR
The disposition of [14C]finasteride, a competitive inhibitor of steroid 5 alpha-reductase, was investigated after oral administration of 38.1 mg of drug in six healthy volunteers and concluded that in humans, finasteride is extensively metabolized through oxidative pathways.
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