Telmisartan: Reversible increased in serum lithium conc & toxicity. Potentiated effect w/ drugs associated w/ K loss & hypokalaemia eg, other kaliuretic diuretics, laxatives, corticosteroids, ACTH, amphotericin, carbenoxolone, penicillin G Na, salicylic acid & derivatives. Increased serum K levels w/ K-sparing diuretics, K supplements, K-containing salt substitutes or other drugs increasing serum K levels eg, heparin Na. Drugs affected by serum K disturbances eg, digitalis glycosides, antiarrhythmics & drugs inducing Torsade de pointes. Reduced diuretic, natriuretic & antihypertensive effects w/ NSAIDs. Increased hypotensive effect of other antihypertensives. Increased median plasma digoxin trough conc. Increased AUC & Cmax
of ramipril & ramiprilat. Hydrochlorothiazide: Potentiated antihypertensive effects by other diuretics, antihypertensives, guanethidine, methyldopa, Ca antagonists, ACE inhibitors, ARBs, DRIs, β-blockers, nitrates, barbiturates, phenothiazines, TCAs, vasodilators or alcohol. Reduced effect w/ salicylates, other NSAIDs eg, indomethacin. Increased hypersensitivity reactions of allopurinol. Increased risk of amantadine-related ARs. Attenuated effect of insulin or oral antidiabetics, uric acid-lowering agents, norepinephrine, epinephrine. Potentiated effects of cardiac glycosides. Increased K loss w/ kaliuretic diuretics (eg, furosemide), glucocorticoids, ACTH, carbenoxolone, penicillin G, salicylates, amphotericin B, antiarrhythmics, laxatives. Increased Na loss w/ natriuretic diuretics, antidepressants, antipsychotics, antiepileptics. Reduced renal excretion of cytotoxic agents eg, cyclophosphamide, fluorouracil, methotrexate. Increased bioavailability w/ anticholinergics eg, atropine, biperiden. Increased plasma lithium levels. Potentiated or prolonged effect of curare-like muscle relaxants. Reduced absorption w/ cholestyramine or colestipol. Reduced Ca excretion w/ vit D. Hypercalcaemia w/ Ca salts. Increased risk of hyperuricaemia & gout-like complications w/ ciclosporin. Increased hyperglycaemic effect of diazoxide. Reduced response to adrenergic amines eg, norepinephrine.