A CONTROVERSIAL drug designed to calm hyperactive children is being peddled in schools to youngsters looking for a cocaine-like high.

Children who have been prescribed Ritalin to combat their Attention Deficit Hyperactivity Disorder (ADHD) are also being bullied to hand over their pills.

Details of the playground trade in the Class B drug were revealed last night by campaigners who are demanding action to halt the problem.

They said Ritalin tablets are changing hands in schools for as little as 50p - either to youngsters looking for a buzz or girls who use it because it suppresses appetite and helps dieting.

Dave Woodhouse, head of psychology at Teesside University, described the trend as "greatly worrying".

Mr Woodhouse helps run the Cactus Clinic in Middlesbrough, which provides non-drug treatment for 50 children with ADHD.

Janice Hill, who runs the drugs advice group Overload Network International, based in Edinburgh, said: "This is happening in schools up and down the country.

"Children given Ritalin are sharing it with their friends because one of the side-affects is it acts as a food suppressant and helps girls achieve the stick insect-like figures they crave.

"Others take it to get a high because if it is crushed up and snorted or kept under the tongue it gives a quick high."

Ms Hill said a group of 13- and 14-year-olds were questioned by police in County Durham after a mother found a pill while she was doing her daughter's washing. She took it to a pharmacist who identified it as Ritalin.

Mr Woodhouse said he had also heard of one boy being found hanging by his underpants from a clothes peg at a Middlesbrough school after having his daily dose of tablets stolen.

"I gave a talk the Wednesday before last to teachers in Middlesbrough and asked how many knew of Ritalin being sold among children at school.

"Ninety per cent of them put their hands up," he said. "That's the scale of the problem."

Dave Johnson, head of inclusion at Middlesbrough Council, said: "We are aware there is a market for them, and sadly, along with a lot of drugs, they can be acquired for a price."

The drug acts as a potent amphetamine and has a similar effect to cocaine, but if it is taken properly and the release of its agents is gradual, it simply calms children down.

It was first used in America to treat ADHD, but it is now on the Drug Enforcement Agency's top ten list of most stolen prescription drugs.

While many parents say it has transformed their child's behaviour, others are alarmed at the side effects, which include sleeplessness, lack of appetite and suppression of growth.

It is recommended for children aged over six, but some as young as three have been referred to the Cactus Clinic having been prescribed the drug by a psychiatrist or paediatrician.

Mr Woodhouse said: "There are kids as young as three, four, five and six who have been prescribed Ritalin.

"It is happening. That's one of the concerns we have."

Janice Hill added: "We are saying to teenagers 'do not take amphetamines, do not take Ecstasy and do not take cannabis' and then we cross over to the NHS and see it is quite acceptable to have amphetamine to control a child's behaviour.

"We are asking, in Scotland, for an all-out ban on psychiatric drugs for all children under six."

New figures show doctors dispensed 254,000 prescriptions of Ritalin last year - compared with 208,500 in 2001 and only 2,000 in 1992.