1766
As heroin addicts sometimes faint while using illicit drugs , doctors might attribute too many episodes of syncope to illicit drug use and thereby underestimate the incidence of TdP in this special population , and the high mortality in this population may , in part , be caused by the proarrhythmic effect of methadone .
 Chemical: heroin; Disease: syncope; Disease: TdP; Chemical: methadone
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: heroin; Disease: syncope; Disease: TdP; Chemical: methadone