Opioids are a class of drugs that include the illegal drug heroin as well as powerful pain relievers available legally by prescription, such as oxycodone (OxyContin®), hydrocodone (Vicodin®), codeine, morphine, fentanyl, and many others. These drugs are chemically related and interact with opioid receptors on nerve cells in the body and brain. Opioid pain relievers are generally safe when taken for a short time and as prescribed by a doctor, but they are frequently misused (taken in a different way or in a greater quantity than prescribed, or taken without a doctor’s prescription) because they produce euphoria in addition to pain relief. Regular use—even as prescribed by a doctor—can produce dependence, and when misused or abused, opioid pain relievers can lead to fatal overdose. The current epidemic of prescription opioid abuse has led to increased se of heroin, which presents similar dangers.
SOURCE: National Institute on Drug Abuse