Interaction between nabumetone--a new non-steroidal anti-inflammatory drug--and the haemostatic system ex vivo.

Twenty-six healthy volunteers were given the non-steroidal anti-inflammatory drug nabumetone (1 g/day p.o.) for 10 days. Platelet aggregation tests in response to adenosine diphosphate, adrenaline, collagen, arachidonic acid, and ristocetin and bleeding time and coagulation screening tests were performed on three occasions: (1) before drug therapy; (2) on the last day of drug therapy, and (3) 5 days after the end of therapy. No significant changes were noted in platelet aggregation, bleeding time, or the coagulation screening tests, except for a significant drop in fibrinogen during therapy and for 1 week after stopping the drug. The lack of any antiplatelet action and minimal effects on the coagulation parameters recommend the drug as a suitable antirheumatic in patients with bleeding disorders. The hypofibrinogenaemic action requires further studies.