Timolol Metabolism in Human Liver Microsomes Is Mediated Principally by CYP2D6

  title={Timolol Metabolism in Human Liver Microsomes Is Mediated Principally by CYP2D6},
  author={Marjo Volotinen and Miia Turpeinen and Ari Tolonen and Jouko Uusitalo and Jukka M{\"a}enp{\"a}{\"a} and Olavi Pelkonen},
  journal={Drug Metabolism and Disposition},
  pages={1135 - 1141}
Timolol has mainly been used topically for the treatment of glaucoma. It has been suggested that the drug is metabolized by cytochrome P450 CYP2D6. The matter has not, however, been extensively studied. The aim here was to tentatively identify timolol metabolites and to determine the P450-associated metabolic and interaction properties of timolol in vitro. Four metabolites were identified, the most abundant being a hydroxy metabolite, M1. The Km value for the formation of M1 was 23.8 μM in… 

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