Increased Bleeding Risk With Concurrent Use of Selective Serotonin Reuptake Inhibitors and Coumarins

New users of coumarins (acenocoumarol or phenprocoumon) from a Dutch linkage system of approximately 2 million subjects. Cases (n=1848) were hospitalized with a primary diagnosis of abnormal major bleeding while taking a coumarin, matched with up to 4 control subjects.

Concurrent use of selective serotonin reuptake inhibitors (SSRIs) or nonsteroidal anti-inflammatory drugs (NSAIDs)

Coumarin users without concurrent SSRI or NSAID use (matched controls)

Hospitalization with a primary diagnosis of abnormal major bleeding (stratified into gastrointestinal and nongastrointestinal bleeding)safety