The effect of St. John’s wort on the pharmacokinetics, metabolism and biliary excretion of finasteride and its metabolites in healthy men
March 2009
in “European Journal of Pharmaceutical Sciences”
TLDR St. John's wort increases finasteride metabolism, reducing its effectiveness; use caution when combining them.
This study investigated the effect of St. John's wort on the pharmacokinetics, metabolism, and biliary excretion of finasteride and its metabolites in healthy men. The results showed that SJW treatment significantly reduced the peak plasma concentration, the area under the plasma concentration-time curve, and the elimination half-life of finasteride. The biliary and urinary excretion of the drug and its metabolites were also affected. The study concluded that SJW treatment induced the metabolism of finasteride and caused a reduced plasma exposure of the drug. Therefore, caution should be exercised when using St. John's wort in combination with finasteride.
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research The effect of St. John’s wort on the pharmacokinetics, metabolism and biliary excretion of finasteride and its metabolites in healthy men
St. John's wort increases finasteride metabolism, reducing its effectiveness; use caution when combining them.