Episode of harmful use of hallucinogens

Essential (Required) Features:

• An episode of use of hallucinogens that has caused clinically significant damage to a person’s physical health or mental health (e.g., Hallucinogen-Induced Mood Disorder), or has resulted in behaviour leading to harm to the health of others.
• Harm to health of the individual occurs due to one or more of the following: (1) behaviour related to intoxication; (2) direct or secondary toxic effects on body organs and systems; or (3) a harmful route of administration.
• Harm to health of others includes any form of physical harm, including trauma, or mental disorder that is directly attributable to behaviour due to Hallucinogen Intoxication on the part of the person to whom the diagnosis of Episode of Harmful Use of Hallucinogens applies.
• Harm to health is not better accounted for by another medical condition or another mental disorder, including another Disorder Due to Substance Use (e.g., Substance Withdrawal).

Note: Harm to the health of the person to whom the diagnosis applies includes injuries caused by behaviour related to intoxication (e.g., impulsive aggressive behaviour, psychomotor impairment leading to injury), acute health problems resulting from substance use (e.g., overdose, acute gastritis, the effects of hypoxia or prolonged hyperactivity or inactivity), and exacerbation or decompensation of pre-existing chronic health problems (e.g., hypertension, liver disease, or peptic ulceration). Harm may also result from a harmful route of administration (e.g., injecting drug use causing blood-borne virus infections, cocaine use causing a perforated nasal septum). The relevant diagnostic codes from other chapters of the ICD-11, including the chapter on Injury, Poisoning or Certain Other Consequences of External Causes, should be used to describe the specific health consequences of the harmful substance use.

Harm to the health of others includes any form of physical harm, including trauma (e.g., impaired driving causing a motor vehicle accident, assaultive behaviour leading to bodily harm to another person) or mental disorder (e.g., Post-Traumatic Stress Disorder arising from an assault by the intoxicated individual) that is directly attributable to behaviour due to substance intoxication on the part of the person to whom the diagnosis of Episode of Harmful Psychoactive Substance Use applies.

Additional Clinical Features:

• There must be explicit evidence of harm to the individual’s physical or mental health, or of substance-related behaviour due to intoxication that has led to harm to the physical or mental health of others. There must also be a clear causal relationship between the harm to health and the episode of hallucinogen use in question.
• The likelihood of harm to self or others due behaviour related to intoxication varies substantially by substance. For example, such behaviour is unlikely to arise from caffeine or nicotine intoxication.
• Hallucinogen use commonly occurs in the context of other mental disorders. An additional diagnosis of Episode of Harmful Use of Hallucinogens can be made if the index episode of hallucinogen use has resulted in clinically significant harm to the individual’s physical health or has exacerbated or triggered an episode of a pre-existing mental disorder (e.g., a Manic or Depressive Episode or a psychotic episode).
• A diagnosis of Episode of Harmful Use of Hallucinogens often signals an opportunity for intervention, typically a low intensity intervention that can be implemented in a wide range of settings that is specifically aimed at reducing the likelihood of additional harmful episodes or of progression to Harmful Pattern of Use or Hallucinogen Dependence.
• As more information becomes available indicating that the episode is part of a continuous or recurrent pattern of hallucinogen use, or if additional harmful episodes occur, a diagnosis of Episode of Harmful Use of Hallucinogens should be changed to Harmful Pattern of Use of Hallucinogens or Hallucinogen Dependence, as appropriate.

Boundary with Normality (Threshold):

• The diagnosis of Episode of Harmful Use of Hallucinogens requires clinically significant harm to the individual’s physical or mental health or that of others. Examples of impact on physical or mental health that would not be considered clinically significant include mild hangover, brief episodes of vomiting, or transient depressed mood.
• A range of social problems may be associated with an episode of substance use that are not sufficiently severe to constitute clinically significant harm to physical or mental health (e.g., missed appointments, arguments with loved ones). Such problems are not a sufficient basis for a diagnosis of Episode of Harmful Use of Hallucinogens.

Boundaries with Other Disorders and Conditions (Differential Diagnosis):

• Boundary with Hazardous Substance Use: Hazardous Substance Use is classified in the chapter on ‘Factors Influencing Health Status or Contact with Health Services’ in the ICD-11 and not in the chapter on Mental, Behavioural, and Neurodevelopmental Disorders. Hazardous Substance Use appreciably increases the risk of harmful physical or mental health consequences to the user or to others to an extent that warrants attention and advice from health professionals, but has not resulted in specific identifiable harm and therefore does not meet the diagnostic requirements for Episode of Harmful Use of Hallucinogens.
• Boundary with Harmful Pattern of Use of Hallucinogens: If the harm to health is a result of a known episodic or continuous pattern of substance use and all other diagnostic requirements are met, a diagnosis of Harmful Pattern of Use of Hallucinogens should be assigned. Substance use is generally considered to be following a pattern if there has been at least episodic or intermittent use over a period of at least 12 months. If harm is caused by use of hallucinogens but no information is available about the pattern or history of substance use, a diagnosis of Episode of Harmful Use of Hallucinogens may be assigned until such time as evidence for a pattern of use is ascertained.
• Boundary with Hallucinogen Dependence: In Hallucinogen Dependence, individuals use hallucinogens persistently despite harm and adverse consequences. Harm caused by such use may be similar to that observed in Episode of Harmful Use of Hallucinogens. However, Hallucinogen Dependence also includes additional features of impaired ability to control use and increasing priority given to the substance use over other activities. Physiological features (e.g., tolerance) may also be present. If all diagnostic requirements for Hallucinogen Dependence are met, Episode of Harmful Use of Hallucinogens should not be assigned.
• Boundary with Hallucinogen Intoxication: Hallucinogen Intoxication is defined by hallucinogen use that results in clinically significant transient hallucinogen-specific symptoms. Recovery from Hallucinogen Intoxication is generally complete and without physical or mental sequelae. If there is continuing damage or harm (e.g., the effects of hypoxia, the effects of prolonged hyperactivity or inactivity, tissue damage) due to an episode of Hallucinogen Intoxication, a diagnosis of Episode of Harmful Use of Hallucinogens may be assigned. If relevant at the time of the clinical encounter (e.g., in emergency settings), Episode of Harmful Use of Hallucinogens may be diagnosed with an associated diagnosis of Hallucinogen Intoxication.
• Boundary with Hallucinogen-Induced Mental Disorders: Hallucinogen-Induced Mental Disorders can be associated with a single episode of hallucinogen use. If a Hallucinogen-Induced Mental Disorder has occurred as a form of harm resulting from a single episode of hallucinogen use, both Episode of Harmful Use of Hallucinogens and the relevant Hallucinogen-Induced Mental Disorder should be diagnosed (e.g., Episode of Harmful Hallucinogen Use with Hallucinogen-Induced Psychotic Disorder).
• Boundary with overdose: When ingestion of psychoactive substances results in symptoms of overdose (e.g., coma; life-threatening cardiac or respiratory suppression), a diagnosis from the grouping of Harmful Effects of Substances in the chapter on Injury, Poisoning or Certain Other Consequences of External Causes should also be assigned.