Carvedilol is a non-selective beta-blocker in common clinical use, used to treat hypertension, heart failure, and angina pectoris symptoms associated with coronary artery disease. Diclofenac is a non-selective anti-inflammatory drug in general use, which is used to treat rheumatic diseases, osteoarthritis, musculoskeletal pain conditions, menstrual pains and migraines, among others. In our recent experiments involving liver cell enzymes, both carvedilol and diclofenac were found to inhibit several cytochrome P450 (CYP) enzymes central to drug metabolism, potentially leading to adverse drug interactions with other drugs metabolized by the same enzyme. The purpose of this study is to investigate the effects of the use of carvedilol and diclofenac on the activity of key CYP enzymes in drug metabolism in healthy volunteers using a low-dose model drug combination covering seven CYP enzymes.
In an open three-phase, randomized, crossover study with 12 healthy volunteers, the subjects will receive a drug combination of caffeine, bupropion, repaglinide, flurbiprofen, omeprazole, dextromethorphan, midazolam and simvastatin and as a premedication either placebo, carvedilol or diclofenac. Blood samples will be collected and carvedilol, diclofenac, caffeine, bupropion, repaglinide, flurbiprofen, omeprazole, dextromethorphan, midazolam and simvastatin pharmacokinetics will be monitored up to 23 hours post dose.