Excited delirium

Excited delirium (ExDS), also known as agitated delirium (AgDS) or hyperactive delirium syndrome with severe agitation, is a widely rejected diagnosis characterized as a potentially fatal state of extreme agitation and delirium.^[1][2] It has typically been diagnosed postmortem in young adult black males who were physically restrained by law enforcement personnel at the time of death.^[3][4]

Mainstream medicine does not recognise the label as a diagnosis: it is not listed in the Diagnostic and Statistical Manual of Mental Disorders or the International Classification of Diseases, and is not recognized by the World Health Organization, the American Psychiatric Association, the American Medical Association, the American Academy of Emergency Medicine,^[5] or the National Association of Medical Examiners.^[6]

Excited delirium diagnosis has been particularly associated with taser use. A 2017 investigative report by Reuters found that excited delirium had been listed as a factor in autopsy reports, court records or other sources in at least 276 deaths that followed taser use since 2000. The Taser manufacturing firm Axon published numerous medical studies promoting the diagnosis along with their product.^[7][8][9]

There have been concerns raised over the use by law enforcement and emergency medical personnel partners to inject sedative drugs, a practice nicknamed "policing by needle,"^[10] citing claims of excited delirium. The drugs ketamine or midazolam (a benzodiazepine) and haloperidol (an antipsychotic) injected into a muscle have sometimes been used to sedate a person at the discretion of paramedics and sometimes at direct police request.^[11] Ketamine can cause respiratory arrest, and in many cases there is no evidence of a medical condition that would justify its use.^[3][12] The term excited delirium is sometimes used interchangeably with acute behavioural disturbance,^[13]: 1 a symptom of a number of conditions which is also responded to with involuntary injection with benzodiazepines, antipsychotics, or ketamine.^{[14][15]: 152}

A 2020 investigation by the United Kingdom Forensic Science Regulator found that the diagnosis should not have been used since it "has been applied in some cases where other important pathological mechanisms, such as positional asphyxia and trauma may have been more appropriate".^[16] In the U.S., neurologists writing for the Brookings Institution called it "a misappropriation of medical terminology, used by law enforcement to legitimize police brutality and to retroactively explain certain deaths occurring in police custody".^[17] The American Psychiatric Association's position is that the term "is too non-specific to meaningfully describe and convey information about a person."^[3] The Royal College of Psychiatrists has deprecated use of excited delirium, recommending non-diagnostic descriptions for highly agitated states such as acute behavioral disturbance.^[18]