INDOMETHACIN, ASPIRIN & MAY BE OTHER NSAIDS REDUCE HYPOTENSIVE EFFECT. HYDROCHLOROTHIAZIDE & OTHER DIURETICS, OTHER ANTIHYPERTENSIVES MAY POTENTIATE ANTIHYPERTENSIVE EFFECT. RAISED SERUM LITHIUM LEVELS, HYPOTENSIVE EFFECT POTENTIATED BY ALCOHOL. INHIBIT TACHYCARDIA PRODUCED BY VASODIATIATORS. CO-ADMINISTRATION OF CYCLO-OXYGENASE INHIBITORS CAUSE REDUCTON IN RENAL FUNCTION. HYPERKALEMIA IS POSSIBLE IF GIVEN WITH POTASSIUM SPARING DIURETICS OR OTHER POTASSIUM SUPPLIMENTS OR POTASSIUM SALTS , CYCLOSPORIN. THE ADVERSE EFFECTS OF ACE INHIBITORS ON KIDNEYS IS POTENTIATED BY CONCURRENT ADMINISTRATION OF NSAIDS & OTHER NEPHROTOXIC DRUGS. INSULIN EFFECT IS POTENTIATED AS WELL AS OF ORAL HYPOGLYCAEMICS. NITRITOID REACTION ( FLUSHING, DIZZINESS, NAUSEA & HYPOTENSION ASSOCIATED WITH FIRST WEEK OF GOLD TREATMENT ) OCCURRED SOON AFTER COMMENCING TREATMENT WITH ACE INHIBITOR. PROBENECID INCREASED PLASMA CONCENTRATION. MARKED HYPOTENSION SEEN IN PATIENTS ON ACE INHIBITORS WHEN THEY WERE GIVEN INTERLEUKIN-3.