Fentanyl

fentanyl - Common brands: Duragesic, Subsys, Abstral

High risk for addiction and dependence. Can cause respiratory distress and death when taken in high doses or when combined with other substances, especially alcohol.

  WebMD: Addicts Try to Avoid Fentanyl, But Many Fail - Potent synthetic opioid now responsible for more than half of overdose deaths, study suggests