The study found drug use increased with each visit

And often the more they travel to the dance resorts, the more drugs they take, the study has shown.

Writing in Addiction Journal, researchers from Liverpool John Moores University also say clubbers who are already taking drugs could be tempted to use new substances.

Report author Professor Mark Bellis said: "Those who are already users go on drug binges or experiment with different drugs and drug combinations."

The report also claims massive increases in cocaine use could also fuel night-time violence, which is already at "epidemic" levels.

Professor Bellis and his team interviewed 846 holidaymakers aged 16-35 as they waited for return flights to the UK from Ibiza in 1999 and repeated it again with 868 visitors in 2002.

They saw a significant increase in the numbers using ecstasy, cocaine, GHB and ketamine in the space of three years, both taking drugs at home and while on holiday.

Consumption of cocaine has risen even faster than that of ecstasy and more cocaine use may increase already epidemic levels of night-time violence Professor Mark Bellis, Liverpool John Moores University

Those taking ecstasy in Ibiza rose from 35% in 1999 to 43% in 2002.

Cocaine use increased from 15% to 25%.

The report also revealed 16% of GHB users had started in Ibiza, rising to 18% for those using ketamine.

The team also found holidaymakers' use of drugs increased with each visit.

Just over a quarter of first-time visitors used cocaine, but this rose to 50% for those on their fourth visit.

'Atmosphere of excess'

The same pattern was seen in all the main drugs, with ecstasy use increasing from 36% in first time visitors in 2002, to 64% by the fourth visit.

Professor Bellis said: "Once abroad, the sense of freedom and atmosphere of excess and experimentation means that some individuals who have never used drugs experiment with ecstasy, cocaine and even new drugs, such as GHB and ketamine."

He also said that the amount of drugs young people use on holiday was much greater than when they are at home, and warned they could be damaging their health and getting into trouble.

"Consumption of cocaine has risen even faster than that of ecstasy and more cocaine use may increase already epidemic levels of night-time violence," he said.

"Urgent action is needed to stop non-users being recruited and existing users moving on to a wider range of substances."