Drug Interactions between heparin and RCK

GENERALLY AVOID: Theoretically, the coadministration of nonsteroidal anti-inflammatory drugs (NSAIDs) and heparin or low molecular weight heparin (LMWH) may potentiate the risk of bleeding. NSAIDs interfere with platelet adhesion and aggregation and may prolong bleeding time in healthy individuals. While these effects are generally slight and of relatively short duration for most NSAIDs (except aspirin) at recommended dosages, they may be of pronounced clinical significance when combined with the inhibitory effects of heparin on the clotting cascade. However, little clinical data exist regarding an actual interaction. In a controlled, randomized prospective study, 60 patients undergoing total hip replacement received enoxaparin (40 mg subcutaneously 12 hours pre- and every 24 hours postoperatively for 10 days) and analgesia with either ketorolac tromethamine (30 mg IM on induction of anesthesia and every 24 hours postoperatively for 4 days) or an opioid plus acetaminophen. The authors reported no significant differences between the two groups for intraoperative blood loss, postoperative drainage, transfusion requirements, bruising, wound oozing, and leg swelling. However, there have been anecdotal reports of hemorrhagic complications in surgical patients treated with NSAIDs alone and in combination with a LMWH. In addition, NSAIDs are known to cause dose-related gastrointestinal bleeding, which may be complicated by anticoagulant therapy.

MANAGEMENT: Until further data are available, products containing NSAIDs, especially if given chronically or in high dosages, should preferably be avoided in patients receiving heparin or LMWH. Close clinical and laboratory observation for bleeding complications is recommended if concurrent therapy is necessary.