Children as young as two are being prescribed drugs for attention deficit hyperactivity disorder (ADHD), psychologists have warned.
Experts say overstretched health workers are going 'straight to medication' instead of offering behaviour therapy and parenting support.
A survey of 136 educational psychologists in 70 local authorities found that 22 per cent were aware of pre-school children taking drugs such as Ritalin.
This is contrary to NICE guidelines which state that such medication shouldn't be given to kids under six.
It also emerged that among school-age children 'medication was felt to be the predominant form of treatment' despite further NICE advice that psychological therapies should be tried before drugs.
The study was carried out by the British Psychological Society's Division of Educational and Child Psychologists.
One of its authors, Vivian Hill, said: "It is almost certainly to do with the fact that the whole of children's mental health services is incredibly underfunded."
Miss Hill, director of professional educational psychology training at the University College London Institute of Education, added: "I have certainly seen reference to children of two and three who have been prescribed medication."
She said these were likely to be 'severe' cases, but she warned of potential risks to children's health.
She said: "We have no idea about the long-term consequences of exposure to this medication."
The Department of Health said: "Children's mental health is a key priority, which is why we've formed a taskforce to look at how we can provide the best possible care, and have invested £54million in improving access to psychological treatments."
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