substance dependence
in DSM–IV–TR, a cluster of cognitive, behavioral, and physiological symptoms indicating continued use of a substance despite significant substance-related problems. There is a pattern of repeated substance ingestion resulting in tolerance, withdrawal symptoms if use is suspended, and an uncontrollable drive to continue use. DSM–IV–TR identifies 10 drug classes associated with dependence: alcohol, amphetamines, cannabis, cocaine, hallucinogens, inhalants, nicotine, opioids, phencyclidines, and sedatives, hypnotics, or anxiolytics. Often used synonymously with the term addiction, substance dependence has been subsumed with substance abuse under the category substance use disorder in DSM–5 and is no longer considered a distinct diagnosis. Also called chemical dependence.