2555
A 62-year-old Caucasian man with atrial fibrillation who was taking warfarin reported an episode of hematochezia; his international normalized ratio (INR) was 1.74.
 adverse event: episode 
Please tell me event type and its trigger word from given type options. Output format is "type: trigger".  Option: adverse event, potential therapeutic event 
Text: {0} 
Answer:
 adverse event: episode 