A reference of commonly used terms related to opioids, substance use, and treatment.
A problematic pattern of opioid use that causes significant impairment or distress. A diagnosis is based on specific criteria such as unsuccessful efforts to cut down or control use, or use resulting in social problems and a failure to fulfill obligations at work, school, or home, among other criteria. Opioid use disorder is preferred over other terms with similar definitions, “opioid abuse or dependence” or “opioid addiction.”
The preferred term is substance use disorder. When referring to opioids, see the Opioid Use Disorder (OUD) definition below and text box discussing the difference between “tolerance,” “dependence,” and “addiction.”
The use of illegal drugs and/or the use of prescription drugs in a manner other than as directed by a doctor, such as use in greater amounts, more often, or longer than told to take a drug or using someone else’s prescription
Natural, synthetic, or semi-synthetic chemicals that interact with opioid receptors on nerve cells in the body and brain and reduce the intensity of pain signals and feelings of pain. This class of drugs includes the illegal drug heroin, synthetic opioids such as fentanyl, and pain medications available legally by prescription, such as oxycodone, hydrocodone, codeine, morphine, and many others. Prescription opioids are generally safe when taken for a short time and as directed by a doctor, but because they produce euphoria in addition to pain relief, they can be misused and have addiction potential.
Injury to the body (poisoning) that happens when a drug is taken in excessive amounts. An overdose can be fatal or nonfatal.