21833
Naltrexone was injected subcutaneously ( 0 . 02 - 2 mg / kg ) or intrathecally ( 0 . 07 mu g / 10 mu l - 350 mu g / 10 mu l ) , while selective mu - antagonist naloxonazine was administered intraperitoneally ( 5 mg / kg ) prior to nociceptive testing .
 Chemical: Naltrexone; Chemical: naloxonazine
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: Naltrexone; Chemical: naloxonazine