Saturable Binding of Finasteride to Steroid 5α-reductase as Determinant of Nonlinear Pharmacokinetics
January 2010
in “Drug Metabolism and Pharmacokinetics”
TLDR Finasteride's effect on hair loss and prostate enlargement depends on its binding to an enzyme, with maximum impact at 0.2 mg dose.
This study investigated the pharmacokinetics and pharmacodynamics of finasteride, a drug used to treat hair loss and prostate enlargement. The study found that the drug's binding to steroid 5α-reductase, an enzyme involved in the production of dihydrotestosterone (DHT), is a determinant of its nonlinear pharmacokinetics. The study also found that the drug's inhibition of 5αR1 is negligible in the dose range up to 1 mg, and that the serum DHT-reducing effect of finasteride reaches its maximum at a dose of 0.2 mg in the case of repeated administration. The study concludes that the time-dependent increase in AUC observed during repeated oral administrations of finasteride may be explained by the saturation of finasteride binding to 5αR2.
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research Saturable Binding of Finasteride to Steroid 5α-reductase as Determinant of Nonlinear Pharmacokinetics
Finasteride's effect on hair loss and prostate enlargement depends on its binding to an enzyme, with maximum impact at 0.2 mg dose.
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