NCIt definition : The neuroadaptation of the body to the presence of an opioid, and is characterized
by the onset of acute symptoms and signs of withdrawal if the opioid is stopped or
an opioid antagonist is administered.;
Alternative definition : NICHD: A physiological state characterized by tolerance to a pharmacological substance
and symptoms of withdrawal if use is abruptly ended.; NCI-GLOSS: A condition in which a person takes a drug over time, and unpleasant physical
symptoms occur if the drug is suddenly stopped or taken in smaller doses.;