ICD-11

Acute and transient psychotic disorder is characterised by acute onset of psychotic symptoms that emerge without a prodrome and reach their maximal severity within two weeks. Symptoms may include delusions, hallucinations, disorganisation of thought processes, perplexity or confusion, and disturbances of affect and mood. Catatonia-like psychomotor disturbances may be present. Symptoms typically change rapidly, both in nature and intensity, from day to day, or even within a single day. The duration of the episode does not exceed 3 months, and most commonly lasts from a few days to 1 month. The symptoms are not a manifestation of another medical condition (e.g. a brain tumour) and are not due to the effect of a substance or medication on the central nervous system (e.g. corticosteroids), including withdrawal (e.g. alcohol withdrawal).

Acute and transient psychotic disorder, multiple episodes should be used to identify individuals experiencing symptoms that meet the diagnostic requirements for acute and transient psychotic disorder and who have experienced similar episodes in the past.

All definitional requirements for Acute and transient psychotic disorder, multiple episodes in terms of symptoms and duration were previously met. Symptoms have ameliorated such that the diagnostic requirements for the disorder have not been met for at least one month, but some clinically significant symptoms remain, which may or may not be associated with functional impairment. The partial remission may have occurred in response to medication or other treatment.