4015
Three subjects ( 2 on sertraline and 1 on placebo ) withdrew from the study because of side effects .
 Chemical: sertraline
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
 Entities: sertraline 
Answer:
 Chemical: sertraline