The World Health Organisation has voted to recognise video game addiction as an official illness despite opposition from academics and industry bodies.
The WHO says that in order for a person to be diagnosed with video game addiction, their behaviour must be "of sufficient severity to result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning".
Last year, the organisation included video game addiction within the 11th revision of its International Classification of Diseases after concerns the gaming industry encouraged compulsive play.
All 194 members of the WHO have now agreed to adopt the revision and it will come into effect on 1 January 2022.
It said that by classifying gaming addiction as an official disease, medical professionals will become more aware and addicts can receive appropriate treatment.
However, the decision has faced fierce opposition from the gaming industry, with some arguing the issue needs more research.
A statement from the Global Video Game Industry Associations read: "We are concerned [the WHO] reached their conclusion without the consensus of the academic community.
"The consequences of today's action could be far-reaching, unintended, and to the detriment of those in need of genuine help."
It also said that the WHO's guidance was not based on "sufficiently robust evidence".
Some experts also agree that there is not enough evidence to define video game addiction as an illness.
A report published in the Journal of Behavioural Addictions, which pointed to by figures in the gaming industry, said there was a "weak scientific basis" for the classification and urged the WHO to be cautious.
Microsoft has said that while more research is needed, the industry has a "great responsibility" to protect users and address concerns over gaming addiction.
The company's head of gaming, Dave McCarthy, told Sky News: "We put a lot of controls in place that parents can leverage to manage things like screen time and game usage.
"And we also think as an industry there is more we can and should do around research and collaboration."
The WHO said its decision was based on "reviews of available evidence and reflects a consensus of experts from different disciplines and geographical regions".