Serotonin Reuptake Inhibitors and Risk of Abnormal Bleeding.

Serotonin reuptake inhibitors (SRIs) increase the risk of abnormal bleeding by lowering platelet serotonin and hence the efficiency of platelet-driven hemostasis; by increasing gastric acidity and possibly gastric ulceration; and by other mechanisms. The upper gastrointestinal tract is the commonest site of SRI-related abnormal bleeding; bleeding at this location may be increased by concurrent nonsteroidal anti-inflammatory drug therapy and by treatment with antiplatelet or anticoagulant drugs. Bleeding at this location may be reduced by concurrent administration of acid-suppressing drugs.