Health professionals are urging for greater regulation on caffeinated energy drinks after a study showed that caffeine-loaded energy drinks are responsible for a rise in people with heart problems, tremors and chest pains.

Research from the University of Sydney and the NSW Poisons Information Centre found that since 2004 the number of calls made to NSW Poisons helpline about energy drinks rose from 12 in 2004 to 65 in 2010 with at least 128 people requiring hospital treatment.

The most common symptoms reported to the helpline were heart palpitations, agitation, tremors and upset stomachs. At least 20 people had symptoms of more serious poisoning, including hallucinations, seizures and interrupted blood flow to the heart.

Food Standards Australia New Zealand says children aged 5 to 12 will experience raised anxiety levels after drinking two cans of cola, while adults will feel anxious after three cups of instant coffee. Caffeine toxicity can resemble amphetamine poisoning and can cause seizures, psychosis, cardiac arrhythmias and in some cases, death.

The study analyzed calls relating to the toxicity of energy drinks made to the NSW Poisons Information Centre over a seven-year period. Teenagers were the most affected by caffeine and more than half of all reported cases were male. There were 62 children between seven months and 10 years that reported to have consumed energy-drinks, with nine children requiring hospitalization. Almost two-thirds of the energy drink related cases were caused by drinking too much Red Bull and V.

NSW Poisons Information Centre director and lead author of study Naren Gunja wrote that energy drinks mixed with alcohol and other stimulants are a serious concern and that as little as 50 mg of caffeine can cause a disturbance in the heart rhythm.

"In overdose, caffeine toxicity can mimic amphetamine poisoning and lead to seizures, psychosis, cardiac arrhythmias and, potentially but rarely, death," Dr. Gunja wrote.

"Given the clear evidence of toxicity and the growing number of hospitalizations . . . health authorities should increase awareness of the problem, improve package labeling and regulate caffeine content."

The study published in the Medical Journal of Australia, has received the support of the Australian Medical Association who has called for greater regulation of energy drinks in Australia. The AMA is calling for an ban on selling energy drinks to children below 18 years old.

"Warning labels would be the very bare minimum that should be done," AMA Victoria vice-president Dr. Stephen Parnis said. "I would think that preventing sales of these drinks to people under 18 is something that we need to look at very seriously. "

The Australian Beverages Council, a group representing the energy drinks industry disagreed with calls of greater regulation. According to the council energy drinks in Australia are already heavily regulated and that the amount of caffeine in energy drinks are comparable to a common cup of coffee.

"Personal responsibility needs to be considered and trying to regulate against the lack of a common sense or over-consumption of a perfectly safe product by 0.00001 per cent of the population isn't a position supported by the industry," council Chief Executive Geoff Parker said in a statement.

"If indeed caffeine over-consumption is the concern of the researchers then the proposed review of labeling and sale provisions should be extended for all cups of coffee, pots of tea and all chocolate bars."