The objective of this study was to examine and evaluate the frequency of

bleeding and serious drug interactions among patients with atrial fibrillation

(AF) treated with oral anticoagulant [Warfarin]. A random sample of 59

patients from Al-Watni government hospital in Nablus with a principal or

secondary discharge diagnosis of AF was identified. All drug and clinical data

were abstracted from the patient\'s files. We excluded patients who were less

than 65 years of age, or left the hospital against medical advice, and those

whose AF was transient or could not be confirmed. Of the original 59 AF

patients, 19 were cliagnosed who were discharged on Warfarin. The mean age

for these patients was 71.7 years. Among the patients discharged on Warfarin,

94.7 % had one or more drug – drug interactions that could lead to increase risk

of bleeding. Many patients discharged on Warfarin were having multiple

interacting drugs. Patient counseling and follow-up monitoring are essential and

should be carried out to minimize the risk of bleeding and other complications.