3448
The feasibility of using labetalol , an alpha - and beta - adrenergic blocking agent , as a hypotensive agent in combination with inhalation anaesthetics ( halothane , enflurane or isoflurane ) was studied in 23 adult patients undergoing middle - ear surgery .
 Chemical: labetalol; Disease: hypotensive; Chemical: halothane; Chemical: enflurane; Chemical: isoflurane
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: labetalol; Disease: hypotensive; Chemical: halothane; Chemical: enflurane; Chemical: isoflurane