Long-term anticoagulant therapy (coumadin) was gradually tapered over a 6-week period in 63 patients, and stopped abruptly in 71. All of these patients had been on coumadin following myocardial infarction. Acareful follow-up showed that there was no difference in the incidence of thrombotic events in the first 6 weeks after discontinuation of therapy, whether this was stopped abruptly or gradually. These results suggest that clinically recognized “rebound” thrombosis does not occur after long-term coumadin therapy is stopped. There appears to be no hazard inherent in stopping long-term coumadin therapy abruptly. A possible exception to this is patients whose therapy must be stopped because of bleeding episodes.