"The non-negligible non-medical use of ketamine started to emerge in the United States of America in the 1980s, in connection with the rave dance scene, and in Western Europe in the 1990s. Hard data from that period are available only for North America and Western Europe, although the non-medical use of ketamine at alternative dance parties on beaches in Goa, India, in that early period has also been reported.111 

"Surveys conducted in Western Europe in the early 1990s suggest that ketamine was used in relatively high doses,112, 113 often in private settings,114 by recreational users wanting to experience the psychedelic effects of the drug rather than its stimulant effects as a dance drug.115 Towards the end of the 1990s, ketamine may have acquired a bad reputation on the European dance scene as a result of it being sold as “ecstasy”, leading to it being used inadvertently116 and having effects that were potentially markedly different from users’ expectations. 

"In the early 2000s, while the use of ketamine was lower than the use of internationally controlled drugs in Europe and was decreasing among young people in the United States,117 a surge in ketamine use was occurring in East and South-East Asia. Also in connection with the dance scene,118 the non-medical use of the substance in Asia was initially documented in China in 1997.119 From the early 2000s, such use was also documented in Hong Kong, China, Taiwan Province of China,120 Macao, China, and Malaysia.121 

"Indicators of ketamine availability rose sharply in that period and the popularity of ketamine in Hong Kong, China, increased so steeply that within three years of the introduction of the substance on the illicit market, it became the first drug of choice among people under 21 years of age.122, 123, 124 In Taiwan Province of China, the popularity of ketamine soared in the early 2000s;125 in a series of surveys among middle- and high-school students in the early 2000s, ketamine was one of the most commonly used drugs, along with “ecstasy”.126, 127 By 2014, 222,000 people, or more than 15 per cent of all registered drug users in China, were officially registered by the police as users of ketamine.128 The non-medical use of ketamine was placing a health burden on Chinese society, as described in a study on ketamine cystitis published in 2015.129"

Source

UNODC. World Drug Report 2023. United Nations publication, 2023.