SOME OF EFFECTS OF ACETYL SALICYLIC ACID ON THE G.I. TRACT ARE ENHANCED BY ALCOHOL. CONCURRENT ADMINISTRATION OF IT AND DIPYRIDAMOLE MAY RESULT IN AN INCREASE IN PEAK PLASMA-SALICYLATE CONCENTRATION & POTENTIATION OF ANTIPLATELET EFFECT. PABA MAY INCREASE SERUM LEVELS. URINARY ALKALISERS, ANTACIDS, CORTICOSTEROIDS MAY INCREASE EXCRETION. CONVERSLY ASPIRIN TOXICITY MAY OCCUR WHEN STEROIDS ARE WITHDRAWN. MAY POTENTIATE THE EFFECTS OF ANTICOAGULANTS, HYPOGLYCAEMICS, METHOTREXATE, PHENYTOIN, VALPROIC ACID, TRICYCLIC ANTIDEPRESSANTS & ZAFIRLUKAST. MAY ANTAGONISE URICOSURICS LIKE PROBENECID & SULPHINPYRAZONE, SPIRONOLACTONE AND TETRACYCLINES. SHORTENS THE TIME TO INDUCE ANAESTHESIA WITH MIDAZOLAM. GRISEOFULVIN REDUCES ASPIRIN ABSORPTION. THE ANTIPLATELET EFFECTS OF ASPIRIN AND CALCIUM CHANNEL BLOCKERS IS POTENTIATED WHEN BOTH ARE USED TOGATHER. INCREASED CHANCES OF BLEEDING, ECHYMOSIS OR BRUSING IS SEEN. CARBONIC ANHYDRASE INHIBITORS LIKE ACETAZOLAMIDE, METOPROLOL & METOCLOPRAMIDE INCREASE ITS ABSORPTION & PLASMA CONCENTRATION. GOLD COMPOUNDS MAY EXACERBATE ASPIRIN INDUCED LIVER DAMAGE. CONCOMITANT USE OF OTHER NSAIDS SHOULD BE AVOIDED BECAUSE OF INCREASED CHANCES OF SIDE EFFECTS.