The National Institute for Health and Clinical Excellence (NICE) said drugs such as Ritalin should be avoided except in severe cases - and must not be given to the under-fives.

The announcement stems from widespread concern that drugs are given too easily to children.

Instead, the guidelines say parent training and education programmes should be offered as a first-line treatment for ADHD, both for pre-school and school age children.

Drugs remain a first option for children over five and young people with severe ADHD but only as part of a comprehensive treatment plan that includes psychological and behavioural interventions.

Mr Hendry backed the guidelines but said attention also needed to be given to diet, especially any contribution artificial colourings and additives could make to hyperactive behaviour in children.

He said, "I have campaigned throughout my time as an MP to stop children being given drugs unless there is no alternative.

"NICE has realised that many of the problems in children with ADHD cannot be solved through drugs. Instead a multitude of avenues need to be tackled in dealing with children with this condition.

"ADHD is a biological condition not a chemical one. Therefore, the first place to start is diet.

"Back in 2003 I introduced a Food Additives and Colourings Bill. This called for clear labelling on all food products which contain colourings and additives.

"It is now widely agreed that part of the cause of hyperactivity is the presence of certain additives and colourings in food specifically targeted at children.

"Recent research from Southampton University showed removing artificial colours from children's foods, including sweets, cakes and drinks, would bring significant health and social benefits.

"Diet is not the main cause but it is undoubtedly a contributory factor."

• Mr Hendry also welcomed NICE's decision to allow a drug which could save the eyesight of thousands to be provided free on the NHS.

Lucentis is used to treat wet age-related macular degeneration (AMD), one of the leading causes of sight loss which affects 26,000 new sufferers each year.

Previously treatment was only made available to those who had lost the sight of one eye and where the sight in the remaining eye was deteriorating badly.

Mr Hendry said Lucentis was a 'highly effective' treatment but is also extremely expensive, costing more than £10,000 for each eye treated.
He said, "Lucentis is an effective drug and will save the sight of thousands of individuals.

"The consultation process went on for two years and led to a postcode lottery with many residents in East Sussex denied treatment just because of where they lived.

"Worst of all was the fact the treatment was only given when the sight in one eye had been lost.

"This is totally abhorrent and I was appalled by cases in my constituency where people lost their sight when it could easily have been saved.

"I welcome the change but wish it had been sooner in coming."