Drug Interaction Report

MONITOR CLOSELY: The concurrent administration of therapeutic doses of heparin (greater than 15 units/kg/hour) and drotrecogin alfa may increase the risk of serious or life-threatening bleeding due to additive or synergistic effects on the clotting cascade. Drotrecogin alfa inactivates blood clotting Factors Va and VIIIa and may prolong the activated partial thromboplastin time (APTT). Most severely ill septic patients are already at a high risk of bleeding due to coagulopathies with prolonged APTT and prothrombin times (PT).

MANAGEMENT: When making the decision to administer drotrecogin alfa, the increased risk of bleeding versus the benefits of therapy should be carefully considered in seriously ill sepsis patients who are concurrently receiving therapeutic heparin (greater than 15 units/kg/hour). Close clinical and laboratory observation for bleeding complications is recommended if concurrent therapy is necessary. In clinical trials, prophylactic low doses of heparin did not appear to affect safety; however, the efficacy of concurrent drotrecogin alfa and heparin in treating sepsis patients has not been determined.