Can you overdose on caffeinated drinks?

An cup or can of a caffeinated beverage may provide a much-needed boost to your day, but your habit can become dangerous if you drink too much of it -- and may possibly lead to death, experts warn.

Anais Fournier is seen in an undated photo.

/ http://rememberanais.com/

Caffeinated beverages, such as energy drinks, have been under the spotlight recently after parents of a 14-year-old girl named Anais Fournier claimed that their daughter died from drinking two Monster Energy Drinks within 24 hours. The Food and Drug Administration then announced it is investigating five deaths and one non-fatal heart attack allegedly caused by Monster Energy Drink.

"Caffeine is the most widely consumed stimulant drug throughout the world. It has varying effects on the central nervous system and cardiovascular systems, as well as other metabolic effects related to the amount ingested," Dr. Robert Glatter, an emergency medicine physician at Lenox Hill Hospital in New York, told CBSNews.com by email.

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FDA investigating alleged Monster Energy drink related deaths

While it may be legal, caffeine is still a psychoactive stimulant, Cleveland Clinic cardiac surgeon Dr. Marc Gillinov told CBSNews.com. Consuming very large amounts of caffeine can lead to caffeine toxicity, which can lead to irritability, hyper aroused states, abnormal heart beat and cardiac arrest.

"Just think about what coffee does and multiply it by 10," he explained.

It takes quite a large amount of caffeine to be dangerous. Caffeine can start causing problems once you consume more than 1 gram of the substance and be lethal at 10 grams, so doctors like Gillinov recommend that people don't consume more than 400 to 500 milligrams a day. For comparison, he said an average cup of tea has about 40 miligrams while a tall cup of Starbucks coffee (12 ounces) has about 260 milligrams of caffeine, though other brands average about 100 milligrams for a regular sized cup.

Glatter said energy drinks can contain up to 170 milligrams of caffeine per 16 ounces.

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Parents sue Monster Energy Drink after daughter's death

Fournier, of Hagerstown, Md., had reportedly consumed a 24-ounce can of Monster Energy Drink at a local mall, before returning the next day and consuming another 24-ounce can -- about 480 milligrams of caffeine. She then went into cardiac arrest.

An autopsy found that Fournier died of cardiac arrhythmia due to caffeine toxicity that impeded her heart's ability to pump blood.

Monster Beverage Corp. has reportedly denied that its product had anything to with Fournier's death.

• Monster Beverage Corp. reportedly denies role in 14-year-old's death
• Monster Energy Drink maker sued for 14-year-old's death
• FDA investigates five deaths, one heart attack linked to Monster Energy Drinks

Gillinov, who was not involved in the Fournier case, pointed out that mitral valve prolapses, which cause problems in the heart valves, are not caused by caffeine. Still, just because caffeine doesn't cause this specific heart problem doesn't mean it's not dangerous.

"Typically 1-3 cups of coffee (80-250 mg) will typically result in increased alertness and a decrease in fatigue with a perceived increase in heart rate (tacyhcardia)," Glatter said. "Higher doses in the range of 250-500 mg can lead to feelings of nervousness, insomnia, mild tremors, or generalized restlessness."

Caffeine can also cause elevated blood sugar, secretion of gastric acid and diarrhea.

"At even higher doses, caffeine can cause a hyperadrenergic syndrome that can lead to significantly elevated blood pressure as well as cardiac arrhythmias, and potentially seizures," Glatter, who is not involved in Fournier's case, added.

The American Academy of Pediatrics recommends that youth and adolescents do not consume energy drinks, and Gillinov wholeheartedly agrees with their statement.

But, what he's more concerned about is when caffeinated beverages are mixed with alcohol, which can often mask the effects. Drinkers who consume alcohol with energy drinks are twice as likely to report being taken advantage of sexually, report taking advantage of someone else sexually, and report riding with a driver who was under the influence of alcohol than those who just drink alcohol straight. They are also three times more likely to binge drink.

"The person who had three alcohol drinks and an energy drink is the same intoxication as a person who had three drinks, but they think they're fine to drive. People need to be worried more about alcohol intoxication than caffeine intoxication."

[vignariik]

well, i dont find this article probably at all. I just recently went on a camping trip over the weekend and ended up drinking 24+ of the 16 ounce cans. Even though i was pretty messed up due to the mass amounts of ginseng caffeine and taurine. If i had the choice, I wouldn't do it again, but other than the HUGE HUGE HUGE crash i had, i was completely fine. So drink up kiddos.

[nubwaxer]

i can't figure out which is the biggest scam: vitamin water, bottled water or energy drinks.

[pharaoh314]

If you have a family history of cardiovascular defects, or if you personally have a history of cardiovascular defects, don't take stimulants. Duh. It's because of these few idiots that don't do their research that the rest of us have to bear the burden of increased government involvement. BTW why are people getting so upset about caffeinated beverages when one of the most prescribed medicines to American youth is Adderall(amphetamines)?

[Zardoz333]

Much ado about nada. Now's the time to buy Monster's stock, when all the sheep think the sky is falling. Statistically how many people drop dead after just drinking a glass of water? She had a pre-existing medical condition and shame on her parents for not monitoring her diet better. Go to http://www.energyfiend.com/death-by-caffeine and type in your weight. It would take 38 cans of Monster to kill a healthy person weighing 90lbs.

[wailinburnin]

I am totally hypertense from drinking three or more cups of strong coffee each day so I can face the boring chore of looking for a job. I can't calm down by consuming any MM edibles even though I'm in Colorado because I will probably face drug testing that may determine my eligibility for a less than living wage job. The choices I'm being given for President want to continue to connect my good name as an American to their immoral, Drone warfare campaign. I want to live my life like a human being, guess I got to be a Yoga Master instead.

[ATR-PHD]

So I suppose we should ban all peanut products. After all as many as 10 deaths occur in the United States annually from peanut allergy, that is 10 times the number of deaths possibly related to consumption of Monster energy drinks. Do we really need to restrict a product that is safely consumed by millions of people in order to protect an infinitesimal but non-zero segment of the population that may be sensitive to stimulants? It is a ridiculous exercise and a waste of resources. It would be more efficient to ban peanut products from the food supply, and I doubt that will happen any time soon.

[Smart_Tech_Girl]

I thought it was perfectly safe to drink massive amounts of the drug called "caffeine", no?

What a shock!

I always encourage all my kids to drink as much of it as humanly possibly. The more, the better.