(Cleveland) - Cuyahoga County Medical Examiner Dr. Thomas Gilson warns that heroin tainted with the painkiller fentanyl is apparently being sold in the area. There were three fatal overdoses on Tuesday and five non-fatal cases reported this week. Fentanyl is an opiate based painkiller. Because it is as much as 80 times stronger than heroin the likelihood of overdose is much greater. Fentanyl has been linked to heroin related deaths recently in Lorain County as well.