Concern over a controversial beverage concoction of caffeine and booze, that some experts say may not even be legal, could be posing a new health threat for the drinks' biggest fans: college-age people.
Two weeks ago, an athletic, otherwise perfectly healthy 19 year-old man arrived at the emergency room at Temple University Hospital in Philadelphia.
"He had chest pains, he was sweaty, short of breath," said Dr. Robert McNamara, who heads the department of emergency medicine.
The patient was suffering a heart attack.
Tests, however, showed the man had none of the usual signs of an unhealthy heart or arteries.
The symptoms were extremely unusual for such a young person, said McNamara, who added they're typically seen in people who overdose on cocaine or speed. After further questioning, the patient admitted he'd been drinking a new type of beverage, which is growing in popularity, which combines high alcohol content with a large dose of caffeine.
"That was the only explanation we had," for the heart attack, said Dr. McNamara.
The drinks—with names like Joose, Torque and Four Loko-- come in large cans covered with colorful graphics that experts and some students say make the alcoholic beverages hard to tell apart from non-alcoholic ones. The drinks sell for about three dollars each.
Four Loko comes in a 23.5 ounce can that contains 2.82 ounces of alcohol, or 12 percent. Experts say you'd have to drink almost six cans of Bud Light beer, or 67.2 ounces, to get the same amount of alcohol.
The drinks also come with a jolt. The fruit punch-flavored Four Loko has 156 milligrams of caffeine. An eight ounce cup of coffee, by comparison, has about 100 milligrams of caffeine. "This is a dangerous product from what we've seen," Dr. McNamara said. "It doesn't have to be chronic use. I think it could happen to somebody on a first time use."
Dr. McNamara said he had never seen a case like this before. And he said he is now hearing from colleagues about similar cases. A growing number of doctors, lawmakers state and federal officials are warning of potentially serious health problems from the drinks, and some experts argue they are illegal under current federal law.
"It is a quick way to get drunk," said Bruce Goldberger, director of toxicology at the University of Florida College of Medicine. "It is popular among young folks. The marketing and packaging has so much to do with it."
Doctor Mary Claire O'Brien of Wake Forest University led a recent study on the effects of combining alcohol and caffeine. She found that compared to college students who drink only alcohol, students who drink booze mixed with energy drinks are twice as likely to be injured, require medical attention or ride with an intoxicated driver. Those students are also more than twice as likely to take advantage of someone sexually.
Why the difference?
O'Brien said mixing a depressant like alcohol with a caffeine stimulant is akin to stepping on the gas and brake of a car at the same time.
"They can't tell that they're drunk," said O'Brien, an associate professor of emergency medicine and public health. "What this behavior gets is a wide awake drunk."
Drinkers like University of Florida sophomore Daniel Patterson noticed the effects the first time he tried Four Loko.