1498
Intravenous cytarabine and methotrexate appear to act synergistically to enhance the potential for central nervous system toxicity .
 adverse effect: central nervous system toxicity, cytarabine; adverse effect: central nervous system toxicity, methotrexate
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: adverse effect 
Text: {0} 
 Entity Pairs:  central nervous system toxicity, cytarabine; central nervous system toxicity, methotrexate 
Answer:
 adverse effect: central nervous system toxicity, cytarabine; adverse effect: central nervous system toxicity, methotrexate