A school has banned high-caffeine energy drinks after pupils as young as 11 were found to be drinking up to three cans a day.
Head teacher Peter Slough – who describes himself as a 'health nut' - said he had taken the stand after finding pupils downing a can on the way to school instead of eating breakfast.
Now kids at Small Heath School in Birmingham who are caught with a can of Red Bull, Monster, Relentless or similar products will have their drink confiscated and face detention if they repeat offend.
Mr Slough told the local paper: "These caffeine drinks, combined with a poor diet, are responsible for the children who find it difficult to sit and concentrate in class.
"We thought we would raise our battle flags. We know, even the little ones, in Year 7, drink them. They become used to it – it becomes a habit and a worry.
"They are energy drinks, they give you a boost, but if you combine them with the sweets children eat, we have a recipe for disaster."
Parents have supported the ban. One said: "My son said several of his classmates have even fallen asleep in lessons when the effect of the Red Bull has worn off.
"It is as harmful as alcohol and has no place in school."
The British Soft Drinks Association, of which Red Bull and its rivals such as Monster and Relentless are members, is also supporting the move.
A spokesman said: "We are clear that energy drinks are not recommended for children."
Mr Slough's action comes in the wake of a call by Government advisor John Vincent, co-founder of food chain Leon who has been tasked with advising on school meals, to ban energy drinks from school.
He said they were as damaging to young people as drugs, adding: "Energy drinks are effectively another form of drugs. The amount of sugar and caffeine in these drinks is effectively allowing drugs into schools. We don't do that and in our view these drinks should not be a part of school life.
"They have hugely damaging effects on children. It affects their ability to concentrate, how they feel, and they have health effects."
Some 500ml drinks contain as much as 160ml of caffeine – the equivalent of four colas. And they also contain 12 teaspoons of sugar.