JOHNS CREEK, Ga. - Most of us have experienced that heart-racing, jumping-out-of-our-skin feeling that comes with downing a few too many cups of coffee.
But caffeine overload in kids is more common than you would think, says Children's Cardiovascular Medicine cardiologist Dr. Eduardo Montana.
The Johns Creek, Ga, heart specialist says he sees 2 or 3 young patients a week with heart-related symptoms from drinking coffee, caffeinated sodas, energy drinks, or all of the above.
"Well it's usually around the spring," Dr. Montana says. "Usually in upperclassmen, juniors, and seniors. Usually during exam time."
But caffeine can be tricky because it's a stimulant.
In very high levels, it can throw off the heart's natural rhythm.
"It's going to cause jitteriness, shakiness, confusion," Montana says. "It's going to cause heart palpitations, arrhythmias."
The case of 16-year old Davis Cripe of South Carolina is an extreme example.
The teen collapsed and died last month, after ingesting a series of caffeinated drinks.
A coroner ruled the teen died of a heart arrhythmia, or irregular heart rhythm, after ingesting, "A large diet Mountain Dew, a cafe latte from McDonald's and also some type of energy drink" in a two-hour period.
Dr. Montana says this is a pretty extreme case.
"When they talk about the amount of caffeine he consumed 2 hours before class, it's remarkable, the amount of liquid he consumed," Montana says. "And the reasons behind that are still unknown."
So, how much caffeine is safe?
Experts say adults should consume no more than 400 milligrams of caffeine a day or about 4 cups of coffee.
Teens, no more than 100 milligrams, or one cup of coffee a day.
The American Academy of Pediatrics recommends teens and children avoid caffeinated beverages altogether.
Once a person crosses the 400-milligram level, complications like insomnia, jitteriness, and palpitations can occur.
In extremely high doses, caffeine can cause dangerous heart rhythm problems, Montana says.
He says teens are often drinking not just coffee drinks, but caffeinated sodas, and energy drinks that can contain almost 250 milligrams a caffeine.
That's two and a half times the recommended limit, which can be risky.
"It's really dose-dependent," he says. "So there may be an adolescent who takes 50 to 100 milligrams a day and gets a sense of euphoria or alertness and then doesn't take any more. But those who consume larger amounts of caffeine are going to require more and more caffeine to get the same level of euphoria and alertness."
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