<unk>  (ABD) is an umbrella term referring to various conditions of medical emergency where a person behaves in a manner that may put themselves or others at risk. It is not a formal diagnosis. Another controversial term, excited delirium, is sometimes used interchangeably with ABD (although according to definitions adopted by the Faculty of Forensic and Legal Medicine of the Royal College of Physicians in England, "only about one-third of cases of ABD present as excited delirium"). According to the Faculty of Forensic and Legal Medicine, ABD can be caused by a number of conditions including psychosis (potentially due to bipolar disorder or schizophrenia), substance abuse, hypoglycemia, akathisia, hypoxia, head injury as well as other conditions. Treatment generally consists of verbal deescalation, voluntary sedation with antipsychotics or benzodiazepine, or involuntary treatment with antipsychotics, benzodiazepines or ketamine through intramuscular injection as a means of chemical restraint through rapid tranquilization possibly combined with physical restraint.
Acute behavioural disturbance
Fatal insomnia
Mass psychogenic illness
Sleeping disorders following traumatic brain injury
Treatment-resistant depression
Masked depression
Chronic hallucinatory psychosis
Excited delirium