6C4G

ICD-11 MMS 2026-01

Disorders due to use of unknown or unspecified psychoactive substances

Description

Disorders due to use of unknown or unspecified psychoactive substances are characterised by the pattern and consequences of psychoactive substance use when the specific substance is unknown or unspecified. These categories may be used in clinical situations in which it is clear that the disturbance is due to substance use but the specific class of substance is unknown. Once the relevant substance is identified, the disturbance should be recoded under the appropriate substance class.

Exclusions from above levels

  • QE62 – Uncomplicated bereavement
  • QE84 – Acute stress reaction

Child codes

  • 6C4G.0 – Episode of harmful use of unknown or unspecified psychoactive substances
  • 6C4G.1 – Harmful pattern of use of unknown or unspecified psychoactive substance
  • 6C4G.2 – Unknown or unspecified psychoactive substance dependence
  • 6C4G.3 – Intoxication due to unknown or unspecified psychoactive substance
  • 6C4G.4 – Withdrawal due to unknown or unspecified psychoactive substance
  • 6C4G.5 – Delirium induced by unknown or unspecified psychoactive substance
  • 6C4G.6 – Psychotic disorder induced by unknown or unspecified psychoactive substance
  • 6C4G.7 – Certain unknown or unspecified psychoactive substance-induced mental or behavioural disorders
  • 6C4G.Y – Other specified disorders due to use of unknown or unspecified psychoactive substances
  • 6C4G.Z – Disorders due to use of unknown or unspecified psychoactive substances, unspecified

Sibling codes

  • 6C40 – Disorders due to use of alcohol
  • 6C41 – Disorders due to use of cannabis
  • 6C42 – Disorders due to use of synthetic cannabinoids
  • 6C43 – Disorders due to use of opioids
  • 6C44 – Disorders due to use of sedatives, hypnotics or anxiolytics
  • 6C45 – Disorders due to use of cocaine
  • 6C46 – Disorders due to use of stimulants including amphetamines, methamphetamine or methcathinone
  • 6C47 – Disorders due to use of synthetic cathinones
  • 6C48 – Disorders due to use of caffeine
  • 6C49 – Disorders due to use of hallucinogens
  • 6C4A – Disorders due to use of nicotine
  • 6C4B – Disorders due to use of volatile inhalants
  • 6C4C – Disorders due to use of methylene-dioxymethamphetamine [MDMA] or related drugs, including methylene-dioxyamphetamine [MDA]
  • 6C4D – Disorders due to use of dissociative drugs including ketamine or phencyclidine (PCP)
  • 6C4E – Disorders due to use of other specified psychoactive substances, including medications
  • 6C4F – Disorders due to use of multiple specified psychoactive substances, including medications
  • 6C4H – Disorders due to use of non-psychoactive substances
  • 6C4Y – Other specified disorders due to substance use
  • 6C4Z – Disorders due to substance use, unspecified

Foundation entity

Disorders due to use of unknown or unspecified psychoactive substances – http://id.who.int/icd/entity/1414319298

Allowed postcoordination axes

Part of: 06: Mental, behavioural or neurodevelopmental disorders