1121
Given that discontinuation of nitrofurantoin and introduction of methylprednisolon therapy significantly lowered liver enzyme levels, restoring most of them to normal, we concluded that this was probably the case of toxic liver damage caused by nitrofurantoin.
 adverse event: caused 
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: caused 