Citalopram Acenocoumarol

A 63-year-old woman taking acenocoumarol 18 mg/ week (INR 1.8) started to take citalopram 20 mg/day and 10 days later noted spontaneous bleeding from her gums the INR had risen to more than 15 (31). She was treated with two units of whole blood and the citalopram was withdrawn. Five days later the INR had returned to the target range. 

Borras-Blasco J, Marco-Garbayo JL, Bosca-Sanleon B, Navarro-Ruiz A. Probable interaction between citalopram and acenocoumarol. Ann Pharmacother 2002 36(2) 345. 

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