Inj: Synergistic effect w/ ASA, dipirydamole, phenylbutazone, indometacin, sulfinpyrazone, probenecid, dextran, ethacrynic acid, dicumarol, cytostatic drugs, aspirin, NSAID, octylsalicylic acid, hydrochloroquine. Counteractive effect w/ antihistamines, digitalis prep, tetracycline, nicotine abuse, ascorbic acid.