4010
From Days 9 to 25 , subjects were randomly assigned to either sertraline ( 12 subjects ) or placebo ( 12 subjects ) ; the sertraline dose was titrated from 50 to 200 mg / day from Days 9 to 16 , and remained at 200 mg / day for the final 10 days of the drug administration period .
 Chemical: sertraline; Chemical: sertraline
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: sertraline; Chemical: sertraline