A college student had difficulty falling asleep. Exhausted, she drank large amounts of coffee to get through the day. She was in a vicious cycle: the coffee that was keeping her awake during the day was preventing her from sleeping at night. A high school student started having hand tremors. He was pulling all-nighters to study for his finals and had been consuming lots of coffee to stay awake. A teenager (who keeps calling me "Mom"!) enjoyed one too many caffeinated soft drinks one night and the next morning had a headache and nausea. Clearly, I have some over-caffeinated patients (and children)!

Teenagers. Caffeine. Surprised? Not if you have been keeping up with Piper Jaffray's biannual survey of teen spending. What's trending is that teens are spending as much money on food and drinks (especially coffee), as they are on clothing. Teens spend about 20 percent of their total spending on each, according to an article on Yahoo Finance! about the most recent survey from fall 2014.

1,3,7-Trimethylpurine-2,6-dione, a.k.a. caffeine, is a central nervous system stimulant. Medically, it is used to treat apnea in premature babies and it is used in combination with ergotamine, aspirin or acetaminophen to treat migraine headaches.

For most of us, however, caffeine is being used "off-label." On a daily basis, we're getting caffeine from coffee, tea, soft drinks, energy drinks, cocoa and chocolate. The Mayo Clinic advises that caffeine is not intended to replace sleep and should not be used regularly for this purpose. It should only be used occasionally to stay alert. Perhaps many of us are overdoing it and need to wake up and smell the decaf.

Children are overdoing it, too. Research published in Pediatrics found that about 3 out of 4 children consume caffeine. Caffeine intake for children from coffee increased from 10 percent to 24 percent in the last decade.

Like all drugs and medicines, caffeine can have adverse effects. The National Poison Data System reported that in 2014, more than 1,600 children in the United States were exposed to high caffeine levels, which were associated with irregular heartbeat, delirium, seizures and other complications. Worse yet …

Caffeine can be fatal. Caffeine powder, usually marketed as a dietary supplement, is pure caffeine. A single teaspoon of powdered caffeine is roughly equivalent to the amount in 25 cups of coffee. Powdered caffeine is often sold over the internet in bulk bags, a major concern of the FDA.

There's a fine line between what is safe and what is lethal; even small amounts can lead to accidental overdose. An 18-year-old teenager from Ohio died from an arrhythmia and seizure after consuming powdered caffeine. His blood caffeine level was 70 micrograms per milliliter (a typical coffee drinker would have 3 to 5 micrograms per milliliter.

How much is too much? The American Academy of Pediatrics recommends that adolescents get no more than 100 mg of caffeine a day, yet the amount of caffeine in just one serving may be close to or over the limit:

  • Regular coffee (8 oz.): 95-200 mg

  • Specialty coffee drink, like latte (8 oz.): 63-175 mg

  • Espresso (1 oz.): 47-75 mg

  • Tea (8 oz.): up to 70 mg

  • Soft drinks (12 oz.): up to 55 mg

  • Energy drinks (2 oz. - 8 oz.): up to 207 mg

My advice for parents:

  • Encourage your children to go decaf.

  • Talk to your children about the dangers of too much caffeine and powdered caffeine.

  • Monitor your children's caffeine consumption.

No one wants teenagers to shop until they drop because of all of the caffeine they're buying!

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