Increased risk of angioedema w/ sacubitril/valsartan, racecadotril, mTOR inhibitors (eg, sirolimus, everolimus, temsirolimus), gliptins (linagliptin, saxagliptin, sitagliptin, vildagliptin). Increased risk of hyperkalaemia w/ aliskiren, K salts, K-sparing diuretics (eg, spironolactone, triamterene or amiloride), ACE inhibitors, AIIA, NSAIDs, heparins, immunosuppressant agents eg, ciclosporin or tacrolimus, trimethoprim & co-trimoxazole (trimethoprim/sulfamethoxazole). Increased risk of hyperkalaemia, worsened renal function, CV morbidity & mortality w/ aliskiren. Increased risk of severe anaphylactoid reactions w/ extracorporeal treatments eg, dialysis or haemofiltration. Increased blood-glucose lowering effects w/ antidiabetics (eg, insulin, oral hypoglycemics). Attenuated antihypertensive effects w/ NSAIDs eg, ASA, COX-2 inhibitors & non-selective NSAIDs. Increased hypotensive effects w/ antihypertensive agents, vasodilators (eg, nitroglycerin, other nitrates or other vasodilators) or other BP-reducing medications (eg, TCAs, barbiturates, phenothiazines). Reduced BP w/ anaesth medicinal products, TCAs, antipsychotics. Reduced reflex tachycardia & increased risk of hypotension w/ anaesth. Reduced effects w/ β-sympathomimetics (eg, isoprenaline, dobutamine). Increased BP & exacerbated intermittent claudication w/ β- & α-adrenoceptors (eg, norepinephrine, epinephrine). Bisoprolol: May worsen heart failure w/ centrally acting antihypertensives (eg, clonidine, methyldopa, moxonidine, rilmenidine). Potentiated AV conduction time & -ve inotropic effect w/ class I antiarrhythmics (eg, quinidine, disopyramide; lidocaine, phenytoin; flecainide, propafenone). Negative influence on contractility & AV conduction w/ verapamil- & diltiazem-type Ca antagonists. Increased risk of hypotension & ventricular pump function deterioration w/ dihydropyridine-type Ca antagonists (eg, felodipine, amlodipine). Potentiated AV conduction time w/ class III antiarrhythmics (eg, amiodarone). Increased AV conduction time & risk of bradycardia w/ parasympathomimetic drugs. Additive systemic effects w/ topical β-blockers (eg, eye drops for glaucoma treatment). Reduced heart rate & increased AV conduction time w/ digitalis glycosides. Increased risk of bradycardia w/ mefloquine. Enhanced hypotensive effects w/ MAOIs (except MAO-B inhibitors). Perindopril: Higher frequency of adverse events w/ ACE inhibitor & ARBs. Increased risk of angioedema w/ estramustine. Reversible increase in serum lithium conc & toxicity. Increased antihypertensive effect w/ baclofen. Excessive reduction in BP w/ non-K-sparing diuretics. Risk of hyperkalaemia w/ K-sparing diuretics (eg, eplerenone, spironolactone). Nitritoid reactions w/ injectable gold (Na aurothiomalate).