The poll found cocaine users are likely to have more sexual partners
More than 50% of young people in Liverpool admit to having taken cocaine, a new report claims.
The finding is part of research that shows an "epidemic" of drug use, with respondents saying they take drugs and drinking to enhance their sex lives.
Researchers from Liverpool John Moores University surveyed youngsters from nine European cities in their study.
Drug and alcohol charity Addaction said the city had been unfairly pinpointed but the findings were not shocking.
The poll was carried out among 1,341 youngsters and was led by Professor Mark Bellis, from the Centre for Public Health at Liverpool John Moores University (LJMU).
It showed a third of men and a quarter of women, aged 16 to 35, drank to increase their chances of having sex.
An "epidemic" of recreational drug use and binge drinking is exposing millions of youngsters to drugs, which increases their chance of unsafe sex and increased sexual partners, experts warned.
The authors said these substances altered their sexual decisions and increased their chances of unsafe and regretted sex.
"For many, substance use has become an integral part of their strategic approach to sex, locking them into continued use," they said.
The cities included were Liverpool, Vienna, Brno in the Czech Republic, Berlin, Athens, Venice, Lisbon, Ljubljana in Slovenia, and Palma, Spain.
But Elliot Elam, spokesperson for Addaction, the UK's largest drugs and alcohol charity, said: "I think this report does pinpoint Liverpool a little unfairly.
"Liverpool was the only British city surveyed and it's like saying Palma is representative of the whole of Spain - it's not.
"Although I'm not totally shocked by the statistics, we know we have a problem as compared to the rest of Europe in some areas.
"Drugs, particularly cocaine, are very prevalent and readily available."
He accepted that people "experiment", but often do not have access to enough information to make proper decisions about what they take.
"There is still an acceptability and cachet to taking cocaine," he said.
"[But] most young won't take drugs in isolation they won't just take cocaine, ecstasy or cannabis, they will take whatever is available."