13939
BACKGROUND : Hydroxyurea is a cytostatic agent used to treat myeloproliferative disorders and long - term treatment is associated with mucocutaneous adverse events and nail hyperpigmentation .
 mucocutaneous adverse events, Hydroxyurea; nail hyperpigmentation, Hydroxyurea
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:
 mucocutaneous adverse events, Hydroxyurea; nail hyperpigmentation, Hydroxyurea