Energy drinks like Red Bull are becoming a growing problem for schoolchildren, according to a UK drug expert.
The drinks have been linked to pupils becoming disruptive and hyperactive and may even cause chest pains and headaches.
The warning comes from Bob Tait who gives drug awareness classes to schools for Drug Education UK. However, Red Bull have stated that the energy drinks are not intended for use by children.
In an interview with Nursing Standard magazine, Mr Tait said that he'd been talking to pupils who regularly use energy drinks. "I will talk to a group and ask them who is drinking energy drinks such as Red Bull and five or six hands will shoot up," he said.
"I came across one boy who was having eight a day. That is too much.
"In some cases parents are giving their children these drinks, but I would say the main source is shopkeepers.
"I don't think there are any schools which actually sell them. But the problem is that they are fashionable drinks.
"It is hard to say in how many schools it is a problem, but it is certainly beginning to cause concern."
Mr Tait's comments come after a school in West Sussex banned Red Bull after staff reported increased bad behaviour in some pupils. However, the National Union of Teachers said they were not aware of any widespread problem caused by energy drinks.
Red Bull claim that their drink improves performance and concentration but it was not aimed at child consumption as children are more sensitive to caffeine than adults.
Energy drinks fast facts
Energy drinks have the equivalent amount of caffeine as one cup of coffee
Caffeine is a stimulant that can relieve the effects of tiredness
Too much caffeine can lead to feelings of anxiousness and physical symptoms such as the shakes and headaches
Overuse of caffeine is linked to high blood pressure and heart conditions
Proper nutrition can provide all the energy the body and mind needs to maintain performance and concentration throughout the day. Contact your local nutritionist to see how to keep you and your child healthy and full of energy.