Moderate
Apixaban × citalopram
Direct oral anticoagulants (factor Xa inhibitors)×SSRI (selective serotonin reuptake inhibitor)
Mechanism
Citalopram, like other SSRIs, impairs primary haemostasis by inhibiting platelet serotonin reuptake. Additively with apixaban, bleeding risk rises, mainly GI.
Symptoms
Gum bleeding, epistaxis, bruising without trauma, black or tarry stools, haematuria. Higher risk in older patients, prior peptic ulcer disease, and chronic kidney disease.
Management
The combination is acceptable. In patients over 65 or with prior peptic ulcer: pantoprazole 20 mg/day. Citalopram also prolongs QT, so cap older patients at 20 mg/day.