In addition to the four symptom domain areas identified in the diagnostic criteria, the assessment of cognition, depression, and mania symptom domains is vital for making crit- ically important distinctions between the various schizophrenia spectrum and other psy- chotic disorders.
Psychotic disorders can occur in association with intoxication with the following classes of substances: alcohol; cannabis; hallucinogens, including phencyclidine and related sub— stances; inhalants; sedatives, hypnotics, and anxiolytics; stimulants (including cocaine); and other (or unknown) substances. Psychotic disorders can occur in association with with- drawal from the following classes of substances: alcohol; sedatives, hypnotics, and anxio- lytics; and other (or unknown) substances.
Some of the medications reported to evoke psychotic symptoms include anesthetics and analgesics, anticholinergic agents, anticonvulsants, antihistamines, antihypertensive and cardiovascular medications, antimicrobial medications, antiparkinsonian medica- tions, chemotherapeutic agents (e.g., cyclosporine, procarbazine), corticosteroids, gastro- intestinal medications, muscle relaxants, nonsteroidal anti-inﬂammatory medications, other over-the-counter medications (e.g., phenylephrine, pseudoephedrine), antidepres- sant medication, and disulfiram. Toxins reported to induce psychotic symptoms include anticholinesterase, organophosphate insecticides, sarin and other nerve gases, carbon monoxide, carbon dioxide, and volatile substances such as fuel or paint.
Prevalence of substance/medication—induced psychotic disorder in the general popula- tion is unknown. Between 7% and 25% of individuals presenting with a first episode of psychosis in different settings are reported to have substance/medication-induced psy- chotic disorder.
The initiation of the disorder may vary considerably with the substance. For example, smoking a high dose of cocaine may produce psychosis within minutes, whereas days or weeks of high-dose alcohol or sedative use may be required to produce psychosis. Alco- hol-induced psychotic disorder, with hallucinations, usually occurs only after prolonged, heavy ingestion of alcohol in individuals who have moderate to severe alcohol use disorder, and the hallucinations are generally auditory in nature.
tures. Persecutory delusions may rapidly develop shortly after use of amphetamine or a similarly acting sympathomimetic. The hallucination of bugs or vermin crawling in or un- der the skin (formication) can lead to scratching and extensive skin excoriations. Cannabis- involves persecutory delusions, marked anxiety, emotional lability, and depersonalization.
The disorder usually remits within a day but in some cases may persist for a few days.
Substance/medication-induced psychotic disorder may at times persist when the offend- ing agent is removed, such that it may be difficult initially to distinguish it from an indepen- dent psychotic disorder. Agents such as amphetamines, phencyclidine, and cocaine have been reported to evoke temporary psychotic states that can sometimes persist for weeks or longer despite removal of the agent and treatment with neuroleptic medication. In later life, poly— pharmacy for medical conditions and exposure to medications for parkinsonism, cardiovas- cular disease, and other medical disorders may be associated with a greater likelihood of psychosis induced by prescription medications as opposed to substances of abuse.
With substances for which relevant blood levels are available (e.g., blood alcohol level, other quantifiable blood levels such as digoxin), the presence of a level consistent with tox- icity may increase diagnostic certainty.
Substance/medication-induced psychotic disorder is typically severely disabling and consequently is observed most frequently in emergency rooms, as individuals are often brought to the acute-care setting when it occurs. However, the disability is typically self- limited and resolves upon removal of the offending agent.