ASPIRIN, DIPYRIDAMOLE, HEPARIN & ANTICOAGULANTS INCREASE RISK OFHAEMORRHAGE ALTHOUGH ALL ARE USED IN COMBINATION SOMETIMES. OTHER DRUGS WHICH AFFECT THE PLATELET FUNCTION DO LIKEWISE, INCLUDING SULPHONAMIDES, ALLOPURINAL, DEXTRANS, QUINIDINE, SEX HORMONES, TETRACYCLINES, VALPROIC ACID & SOME ESSENTIAL OILS.