Ritalin 'may cause damage to brains'

Children given Ritalin to control hyperactivity could be permanently brain damaged, it was claimed yesterday.

Research suggests the controversial 'chemical cosh' drug raises the risk of depression and anxiety in adulthood.

Ritalin alters the brain's chemical composition so that it has a lasting effect on mental health, US scientists believe. Because these changes take place while a child's brain is growing, they could cause irreversible damage.

The findings will alarm parents using the drug to control a child's attention deficit hyperactivity disorder (ADHD).

British GPs dispensed a record 254,000 Ritalin prescriptions last year, up from 208,500 in 2001. One in 20 children is said to have ADHD, which makes them boisterous and unfocused.

'It is vitally important we evaluate the long-term effects of these drugs,' said Dr Nora Volkow, director of the US National Institute on Drug Abuse.

Although American studies involved laboratory rats, the doses given were comparable to those used on children.

In one test, giving Ritalin to young, healthy rats increased the presence of certain chemicals linked to depression in adults. Asecond study found higher levels of stress hormones and anxietylike behaviours.

Last night, Shadow children's minister Tim Loughton urged the Government to investigate Ritalin use.

The Royal College of Paediatrics said: 'Ritalin has been used for 40 years. If there was a long-term side-effect, it would have been discovered by now.'

Novartis, the company which makes Ritalin, insisted there was no clinical link to depression or anxiety disorders.