Amlodipine: Increased plasma conc by strong or moderate CYP3A4 inhibitors [eg, PIs, azole antifungals, macrolides (eg, erythromycin or clarithromycin), verapamil or diltiazem]. Plasma conc may be decreased by CYP3A4 inducers (eg, rifampicin,
Hypericum perforatum). Risk of increased tacrolimus blood levels. May increase simvastatin plasma level. Bisoprolol:
-ve influence on contractility, AV conduction & BP w/ Ca antagonists of verapamil type & to a lesser extent of diltiazem type. Possible profound hypotension & AV block w/ verapamil IV. Potential reduction of heart rate, cardiac output & vasodilation w/ centrally acting antihypertensive drugs (eg, clonidine, methyldopa, moxonodine, rilmenidine). May increase risk of hypotension & further deterioration of the ventricular pump function in patients w/ heart failure by dihydropyridine type Ca antagonists (eg, nifedipine). May potentiate AV conduction time & -ve inotropic effects w/ class I antiarrhythmics (eg, disopyramide, quinidine, lidocaine, phenytoin, flecainide, propafenone). May potentiate AV conduction time w/ class III antiarrhythmics (eg, amiodarone). May increase AV conduction time & risk of bradycardia w/ parasympathomimetics. Additive systemic effects w/ topical β-blocker-containing prep (eg, eye drops for glaucoma). Intensified blood sugar lowering effect of insulin & oral antidiabetics. Attenuated reflex tachycardia & increased hypotension risk w/ anaesth agents. Reduction of heart rate, increased AV conduction time w/ digitalis glycosides. Hypotensive effect may be reduced by NSAIDs. Potential mutual reduced effect w/ β-sympathomimetics (eg, isoprenaline, dobutamine). May unmask α-adrenoceptor-mediated vasoconstrictor effects of sympathomimetics activating both β- & α-adrenoceptors (eg, norepinephrine, epinephrine) leading to BP increase. Risk of hypotension may be increased w/ antihypertensive agents as well as other drugs w/ BP lowering potential (eg, TCAs, barbiturates, phenothiazines). Increased risk of bradycardia by mefloquine. Enhanced hypotensive effect; risk for hypertensive crisis w/ MAOIs (except MAO-B inhibitors). Slight t
½ reduction by rifampicin. Exacerbation of peripheral circulatory disturbances by ergotamine derivatives.