Green Tea Compounds May Decrease Effectiveness of Blood Pressure Drug

A compound in green tea may prevent the body from absorbing nadolol, a β-blocker used to treat high blood pressure, researchers have found. The study followed 10 adults who drank 3 cups of green tea for 2 weeks before taking nadolol. Participants then switched to drinking water before taking nadolol. After drinking green tea, blood levels of nadolol were 76% lower than levels measured after drinking water. Urine levels were about 80% lower. Additional experiments suggest that EGCG, an antioxidant in green tea, inhibits proteins that transport nadolol into cells. The findings are published in Clinical Pharmacology & Therapeutics.