Green tea ingestion greatly reduces plasma concentrations of nadolol in healthy subjects

Clin Pharmacol Ther. 2014 Apr;95(4):432-8. doi: 10.1038/clpt.2013.241. Epub 2014 Jan 13.


This study aimed to evaluate the effects of green tea on the pharmacokinetics and pharmacodynamics of the β-blocker nadolol. Ten healthy volunteers received a single oral dose of 30 mg nadolol with green tea or water after repeated consumption of green tea (700 ml/day) or water for 14 days. Catechin concentrations in green tea and plasma were determined. Green tea markedly decreased the maximum plasma concentration (C(max)) and area under the plasma concentration-time curve (AUC(0-48)) of nadolol by 85.3% and 85.0%, respectively (P < 0.01), without altering renal clearance of nadolol. The effects of nadolol on systolic blood pressure were significantly reduced by green tea. [(3)H]-Nadolol uptake assays in human embryonic kidney 293 cells stably expressing the organic anion-transporting polypeptides OATP1A2 and OATP2B1 revealed that nadolol is a substrate of OATP1A2 (Michaelis constant (K(m)) = 84.3 μmol/l) but not of OATP2B1. Moreover, green tea significantly inhibited OATP1A2-mediated nadolol uptake (half-maximal inhibitory concentration, IC(50) = 1.36%). These results suggest that green tea reduces plasma concentrations of nadolol possibly in part by inhibition of OATP1A2-mediated uptake of nadolol in the intestine.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-Antagonists / pharmacokinetics*
  • Adrenergic beta-Antagonists / pharmacology
  • Adult
  • Area Under Curve
  • Blood Pressure / drug effects
  • Catechin / pharmacokinetics*
  • Cross-Over Studies
  • Female
  • Food-Drug Interactions*
  • HEK293 Cells
  • Humans
  • Inhibitory Concentration 50
  • Intestinal Mucosa / metabolism
  • Male
  • Nadolol / pharmacokinetics*
  • Nadolol / pharmacology
  • Organic Anion Transporters / metabolism
  • Tea / chemistry*
  • Young Adult


  • Adrenergic beta-Antagonists
  • Organic Anion Transporters
  • SLCO1A2 protein, human
  • SLCO2B1 protein, human
  • Tea
  • Nadolol
  • Catechin