In Vitro Selective Inhibition of Human UDP-Glucuronosyltransferase (UGT) 1A4 by Finasteride and Prediction of In Vivo Drug–Drug Interactions

    January 2015 in “ Toxicology Letters
    Seung Hwan Lee, Jung Tak Park, Do-Yun Kim, Soo Kyung Bae, Young-Won Chin, Euichaul Oh
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    TLDR Finasteride affects UGT1A4 enzyme, but not enough to cause issues when combined with other drugs.
    The study found that finasteride selectively inhibits the UGT1A4 enzyme in vitro, which could potentially lead to drug-drug interactions in vivo. However, the in vivo concentration of finasteride is not high enough to cause significant inhibition of UGT1A4. The study suggests that caution should be taken when administering drugs that are metabolized by UGT1A4 in combination with finasteride.
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