According to self-report surveys, energy drinks are consumed by 30 percent to 50 percent of adolescents and young adults. Of the 5,448 U.S. caffeine overdoses reported in 2007, 46 percent occurred in those younger than 19 years old.

The problem is not just an American one. Several countries and states have debated or restricted their sales and advertising. Denmark, Turkey and Uruguay have banned them; Norway prohibits sales to children under 15.

One review of the effects of high-caffeine energy drinks on children and young adults found that they have been linked to an array of serious events like heart palpitations, high blood pressure, cardiac arrest and death. They may also pose additional risks to young people who take medication or have chronic illnesses.

A study published in the journal Pediatrics, urges pediatricians to discuss the risks of energy drinks with patients, especially those with heart conditions and mood or behavioral disorders, like attention deficit hyperactivity disorder.

The high amounts of sugar can also pose risks to those with diabetes. Last October, the National Federation of State High School Associations cautioned that caffeinated energy drinks (which are often confused with products like Gatorade, a fluid replacement drink) should not be consumed before, during or after physical activity because they could raise the risk of dehydration and increase the chance of potentially fatal heat illnesses.

Experts say energy drinks have no therapeutic benefit, and many ingredients are understudied and not regulated. The known and unknown pharmacology of agents included in such drinks, combined with reports of toxicity, raises concern for potentially serious adverse effects in association with energy-drink use.

In the short-term, pediatricians need to be aware of the possible effects of energy drinks in vulnerable populations and screen for consumption to educate families. Long-term research should aim to understand the effects in at-risk populations. Toxicity surveillance should be improved, and regulations of energy-drink sales and consumption should be based on appropriate research.

An average energy drink contains 70 to 80 milligrams of caffeine per eight-ounce serving. That’s about three times the concentration of some sodas, but may derive extra caffeine from other ingredients, like kola nut, cocoa and guarana.

The trade group, American Beverage Association, says the study presents misinformation about energy drinks, and that an average energy drink contains only half the caffeine of a cup of coffeehouse coffee.