4177
Prolonged infusion of dexmedetomidine , an alpha ( 2 ) - adrenoreceptor agonist anesthetic used in the intensive care unit , produces a withdrawal syndrome of sympathetic over - activity , characterized by tachycardia , hypertension and agitation , but there is no recommended standard treatment for this syndrome .
 Chemical: dexmedetomidine
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: dexmedetomidine 
Answer:
 Chemical: dexmedetomidine