Due to the ambiguity of the term “abuse”, the WHO Lexicon has replaced this term with “harmful use” and “hazardous use”, which promote clarity and reduce stigma.
This refers to the use of a psychoactive substance in a way that causes, or increases the risk of causing, harm to health or well-being.
Harmful use involves patterns of consumption that lead to physical or mental health problems, such as liver disease (e.g. Hepatitis following injection of a drug) or depression (e.g. secondary to heavy alcohol intake), and may also result in social or behavioural difficulties.
Hazardous use, on the other hand, describes patterns of substance use that elevate the likelihood of harmful outcomes, even when no current disorder is evident.
In international contexts, this concept also includes the use of controlled substances beyond medical or therapeutic purposes, in excessive amounts or for longer durations than justified.
Sources: UNODC