There are around 20 drugs for treating ADHD (attention-deficit, hyperactive disorder) in children-but their long-term effectiveness, safety or even the adverse reactions they may cause were never tested when they were approved.
Although 11 per cent of children in the US-which amounts to around 6.4 million children and adolescents-are regularly taking the drugs.
But when the drugs were approved by America's drug regulator, the Food and Drug Administration (FDA), almost none of the initial trials focused on safety, the average study involved just 75 people, and with an average duration of just four weeks, even though the children are supposed to take the drugs their entire childhood.
Seven of the 20 drugs approved by the FDA weren't even designed to treat ADHD, but instead were supposed to target other health problems such as obesity.
Researchers from the Boston Children's Hospital say the bar needs to be raised higher before approval is given. The drugs should be tested on up to 600 people for at least six months, in a minimum of 100 patients for at least one year, and in about 1,500 people in total before regulatory approval is given.
(Source: PLoS ONE, 2014; 9(7): e102249)