Additive hypotensive effect w/ prazosin, terazosin. Additive effects reducing myocardial contractility, prolonging AV conduction & prolonging repolarization w/ flecainide. Hypotension w/ quinidine. Reduced clearance w/ theophylline, digitoxin. Increased levels of carbamazepine, tacrolimus, atorvastatin, lovastatin. Decreased plasma conc w/ phenytoin. Increased AUC of imipramine, sirolimus. Increased Cmax
& AUC of glyburide, colchicine, doxorubicin, buspirone, midazolam, everolimus, simvastatin, almotriptan. Possible increased levels w/ clarithromycin, erythromycin, telithromycin. Reduced BP lowering effect w/ rifampicin, sulfinpyrazone. Increased clearance w/ phenobarb. Slowed AV conduction w/ digoxin. Increased AUC, Css
of cyclosporine. Additional heart rate lowering effect of ivabradine. Increased AUC w/ grapefruit juice. Decreased AUC w/ St. John's wort. Increased plasma conc w/ HIV antivirals (eg, ritonavir). Increased neurotoxicity w/ lithium. May potentiate the activity of neuromuscular-blocking agents (eg, curare-like & depolarizing). Increased tendency to bleed w/ ASA. Elevation of ethanol plasma levels. Potentiation of the hypotensive effects of antihypertensives, diuretics, vasodilators. Tab: Increased risk of bleeding w/ dabigatran. Increased absorption of direct oral anticoagulants. Inj: Exaggerated hypotensive response w/ agents that decrease adrenergic function. May depress myocardial contractility or AV conduction w/ β-blockers (eg, metoprolol, propranolol). Reduced clearance w/ cimetidine. Risk of CV depression w/ inhalation anesth. Protein bound drugs.