The number of children being prescribed for the hyperactivity drug Ritalin is subject to huge variations across primary care trusts (PCTs) in England, according to figures.
The Health Service Journal (HSJ) reported that it had seen official figures on the prescribing rates of different PCTs.
It used this data, together with Office for National Statistics figures, to work out the number of prescriptions per 1,000 children in each PCT area.
The highest figure was seen across the Wirral PCT, with 144 prescriptions written for every 1,000 children in its area in 2007.
Meanwhile, Stoke on Trent had the lowest rate, with six for every 1,000 children in its area.
The Department of Health said the figures, issued by Care Services Minister Ivan Lewis, were estimated dispensing figures based on a sample of one in 20 prescription items.
It said the figures could be subject to sampling errors, for example some PCTs may prescribe weekly while others do so monthly.
There is dispute about whether the medicine, used to treat children with attention deficit hyperactivity disorder (ADHD), works in the long-term. A study obtained by the BBC's Panorama programme last year found Ritalin worked no better than therapy after three years of treatment.
It said that the benefits of drugs had previously been exaggerated.