3479
During the 14 - day run - in and during washout periods , inhaled beta - agonists were withheld and ipratropium bromide was substituted for rescue purposes .
 Chemical: ipratropium bromide
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: ipratropium bromide