QE11.9

ICD-11 MMS 2026-01

Hazardous use of unknown or unspecified psychoactive substances

Description

A pattern of use of unknown or unspecified psychoactive substances that 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. The increased risk may be from the frequency of use of the substance, from the amount used on a given occasion, from risky behaviours associated with use of the substance or the context of use, from a harmful route of administration, or from a combination of these. The risk may be related to short-term effects of the unknown or unspecified substance or to longer-term cumulative effects on physical or mental health or functioning. Hazardous use of unknown or unspecified psychoactive substances has not yet reached the level of having caused harm to physical or mental health of the user or others around the user. The pattern of substance use often persists in spite of awareness of increased risk of harm to the user or to others.

Index terms

  • Hazardous use of unknown or unspecified psychoactive substances

Excludes

  • 6C4G – Disorders due to use of unknown or unspecified psychoactive substances

Exclusions from above levels

  • http://id.who.int/icd/entity/590211325 – Disorders due to substance use
  • QF21 – Difficulty or need for assistance with general life tasks or life management

Sibling codes

  • QE11.0 – Hazardous use of opioids
  • QE11.1 – Hazardous use of cannabis
  • QE11.2 – Hazardous use of sedatives, hypnotics or anxiolytics
  • QE11.3 – Hazardous use of cocaine
  • QE11.4 – Hazardous use of stimulants including amphetamines or methamphetamine
  • QE11.5 – Hazardous use of caffeine
  • QE11.6 – Hazardous use of MDMA or related drugs
  • QE11.7 – Hazardous use of dissociative drugs including ketamine or PCP
  • QE11.8 – Hazardous use of other specified psychoactive substances
  • QE11.Y – Other specified hazardous drug use
  • QE11.Z – Hazardous drug use, unspecified

Foundation entity

Hazardous use of unknown or unspecified psychoactive substances – http://id.who.int/icd/entity/1240119257

Part of: QE11: Hazardous drug use › 24: Factors influencing health status or contact with health services