Other (or Unknown) Substance Use Disorder 579
Diagnostic Features
The diagnostic class other (or unknown) su bstance use and related disorders comprises
substance-related disorders unrelated to alco hol; caffeine; cannabis; hallucinogens (phen-
cyclidine and others); inhalants; opioids; sedative, hypnotics, or anxiolytics; stimulants
(including amphetamine and cocaine); or tobacco. Such substances include anabolic ste-
roids; nonsteroidal anti-inflammatory drugs; cortisol; antiparkinsoni an medications; an-
tihistamines; nitrous oxide; amyl-, butyl-, or isobutyl-nitrites; betel nut, which is chewed
in many cultures to produce mild euphoria an d a floating sensation;  kava (from a South
Pacific pepper plant), which produces sedation , incoordination, weight loss, mild hepati-
tis, and lung abnormalities; or cathinones (including khât plant agents and synthetic chem-
ical derivatives) that produce stimulant effe cts. Unknown substance- related disorders are
associated with unidentified substances, such as intoxications in which the individual can-
not identify the ingested drug, or substance use disorders involving either new, black mar-
ket drugs not yet identified or familia r drugs illegally sold under false names.
Other (or unknown) substance use disorder is  a mental disorder in which repeated use
of an other or unknown substance typically continues, despite the individual’s knowing
that the substance is causing serious problems  for the individual. Th ose problems are re-
flected in the diagnostic criteria . When the substance is known, it should be reflected in the
name of the disorder upon coding (e.g., nitrous oxide use disorder).
Associated Features Supporting Diagnosis