Clinical symptoms and brain changes seen in substance use disorders have also been observed in particular behaviours, leading to the concept of ‘behavioural addiction’.

Gambling disorder and gaming disorder are now classified by the World Health Organisation alongside substance use disorders

In the future other behaviours, such as harmful use of internet pornography, may join gaming and gambling disorders.

Like substance use disorders, behavioural addictions can lead to harms for the individual including worsening mental health, social function and academic performance.

Relatives, friends and others can also suffer consequences of behavioural addictions such as financial loss (with gambling disorder) and deteriorating relationships.

The evidence on how best to treat behavioural addiction are still building, but approaches used for substance use disorders are typically recommended.