Assertion: methadone's use | /r/HasSubevent | reduced efficacy of methadone
Facets:
Source sentences:
text: Concurrent use of methadone and drugs that induce cytochrome P450 enzymes (such as rifampicin, phenytoin, phenobarbital, carbamazepine, and St. John’s Wort) may result in reduced efficacy of methadone and could precipitate a withdrawal syndrome.