`` This is not accidental , '' Pittsburgh medical examiner says . Fentanyl is used to treat pain in cancer patients . Dr. Karl Williams says he normally sees three or four deaths from drug overdoses in a typical week as the chief medical examiner in Pennsylvania 's Allegheny County , which includes Pittsburgh . Comment:
`` This is not accidental , '' Pittsburgh medical examiner says . Fentanyl is used to treat pain in cancer patients . Comment: