Pubdate: Mon, 20 Apr 1998 Source: The Age Contact: http://www.theage.com.au/ Author: Leigh Dayton MEDICINE MAY ENCOURAGE COCAINE USE Concern is growing that a drug given to millions of hyperactive children worldwide may prime their brains for drug abuse later in life. Some researchers in the United States fear that the leading treatment for attention deficit hyperactivity disorder (ADHD), methylphenidate marketed as Ritalin, affects the brain like cocaine. As a result, they suggest that cocaine may have a bigger impact on people who were treated with the drug, thereby increasing the likelihood they will "develop a taste for cocaine", New Scientist magazine reported at the weekend. In Australia, the National Health and Medical Research Council has estimated that between 2 and 6 per cent of children, mostly boys, are affected by the disorder. Sufferers often find it difficult to concentrate and are prone to fidgeting, impulsive movements and clumsiness. According to New Scientist, animal experiments and a study of just how and where Ritalin works in the human brain support the claim that it may encourage cocaine use. A long-term study of 5000 Californian adolescents with the disorder found that, as adults, those treated with Ritalin were three times more likely to use cocaine - although they were no more likely to abuse alcohol or marijuana - than those who did not take the medication. The research was conducted by a pharmacologist, Dr Susan Schenk, at Texas A & M University and a psychologist, Dr Nadine Lambert, of the University of California. Australian experts greeted the suggestion that Ritalin may be linked to cocaine abuse with caution. Although she said the possibility "certainly requires further work", University of New South Wales Associate Professor Florence Levy, head of the Avoca Clinic at the Prince of Wales Department of Child and Adolescent Psychiatry, said that for many children the benefits of Ritalin outweighed the potential risks. Dr Christopher Green, director of the Child Development Unit at the New Children's Hospital, went further, pointing to a study of high school students in the US which found those treated with the medication were less likely to drop out of school and abuse drugs than those who did not receive treatment.