8945
The day after methotrexate administration , the patient complained of severe back pain and urinary retention .
 severe back pain, methotrexate; urinary retention, methotrexate
Please list all entity pairs containing a certain relationship in the given options.Output format is "word1, word2; word3, word4". 
Option: adverse effect 
Text: {0} 
Answer:
 severe back pain, methotrexate; urinary retention, methotrexate