ALCOHOL, BARBITURATES, OR NARCOTICS --POTENTIATION OF ORTHOSTATIC HYPOTENSION MAY OCCUR. IT POTENTIATES ANTI-HYPERTENSIVES, CAUTION IN PATIENT TAKING DIGOXIN. INCREASED RISK OF HYPOKALEMIA WITH CORTICOSTEROIDS, CORTICOTROPHINS, BETA 2 AGONISTS LIKE SALBUTAMOL, CARBENOXOLONE, AMPHOTERICIN-B. DOES OF ORAL ANTIDIABETIC AGENTS MAY NEED TO BE RAISED. PROBENECID COMPETITIVELY INHIBITS TUBULAR SECRETION. IT MAY ENHANCE NEUROMUSCULAR BLOCKING ACTION OF TUBOCURARINE LIKE DRUGS. CONCOMITANT USE OF LITHIUM, ALLOPURINOL, TETRACYCLINE MAY LEAD TO TOXIC BLOOD LEVELS OF THESE DRUGS. DOSAGE ADJUSTMENTS OF ANTICOAGULANT MEDICATION MAY BE NECESSARY SINCE BENDROFLUMETHIAZIDE MAY DECREASE THEIR EFFECTS. CHOLESTYRAMINE RESIN AND COLESTIPOL HCL --MAY DELAY OR DECREASE ABSORPTION OF BENDROFLUMETHIAZIDE. DIAZOXIDE --ENHANCED HYPERGLYCEMIC, HYPERURICEMIC, AND ANTIHYPERTENSIVE EFFECTS. MAO INHIBITORS --DOSAGE ADJUSTMENTS OF ONE OR BOTH AGENTS MAY BE NECESSARY SINCE HYPOTENSIVE EFFECTS ARE ENHANCED. NONSTEROIDAL ANTI-INFLAMMATORY AGENTS --IN SOME PATIENTS, THESE CAN REDUCE THE DIURETIC, NATRIURETIC, AND ANTIHYPERTENSIVE EFFECT OF LOOP, POTASSIUM-SPARING OR THIAZIDE DIURETICS. PROBENECID OR SULFINPYRAZONE --INCREASED DOSAGE OF THESE AGENTS MAY BE NECESSARY SINCE BENDROFLUMETHIAZIDE MAY HAVE HYPERURICEMIC EFFECTS. METHENAMINE --POSSIBLE DECREASED EFFECTIVENESS DUE TO ALKALINIZATION OF THE URINE. CALCIUM EXCRETION IS DECREASED BY DIURETICS .