Opiate: A medication or an illegal drug that is derived from the opium poppy or that mimics the effect of an opiate (a synthetic opiate). Opiate drugs are narcotic sedatives that depress activity of the central nervous system, reduce pain, and induce sleep. Side effects may include oversedation, nausea, and constipation. Long-term use of opiates can produce addiction, and overuse can cause overdose and potentially death.
Last Editorial Review: 5/13/2016