How does your daily dose of caffeine stack up?

The sudden death of an otherwise healthy 16-year-old Spring Hill High School student has stunned coffee and energy-drink consumers nationwide and left many wondering: How much caffeine is too much?

Davis Allen Cripe collapsed in April while in a classroom from a “caffeine-induced cardiac event” that caused “a probable arrhythmia,” after he drank a latte, a bottle of diet soda and energy drink in a two-hour period, said Richland County Coroner Gary Watts on Monday.

The results have triggered a conversation surrounding the daily caffeine intake of Americans. Questions surrounding the issue are not surprising, because it’s rare for people to suffer from serious toxicity from caffeine, said William Richardson, an emergency medicine physician at Palmetto Health Richland and medical director of the Palmetto Poison Center.

“People drink several cups of coffee several times a day and don’t have a problem,” Richardson said.

Richardson stressed he was unfamiliar with Cripe’s case, because the poison center was not consulted. In general, however, he said poison control centers nationwide in 2015 reported more than 3,000 calls related to caffeine-containing energy drinks.

The Palmetto Poison Center has averaged between 60 and 80 phone calls every year for the past three years from people reporting problems after ingesting large amounts of caffeine, said Jill Michels, managing director of the center.

Michels said people sometimes have a hard time tracking how much caffeine they’re taking daily, because the products’ labels can be confusing.

And “sometimes it’s hidden in products that we don’t even think about,” Michels said.

The majority of Americans consume caffeine through coffee, soft drinks and tea, according to the Food and Drug Administration. And the average adult consumes about 300 milligrams a day.

Studies have shown that ingesting up to 400 milligrams daily – which adds up to about four cups of coffee – appears to be safe in most healthy adults, according to the Mayo Clinic. But caffeine levels in 8 ounces of soda vary between 24 and 46 milligrams, depending on the brand and whether it’s diet or regular.

A 20-ounce bottle of Diet Mountain Dew, for example, contains 91 milligrams of caffeine. Though Watts did not say how many ounces Cripe consumed on the day he died, he did say a “large” bottle of Mountain Dew was part of the caffeine combination that induced the “cardiac event.”

And sometimes people don’t account for caffeine-like chemicals in energy drinks and booster shots such as guarana, cola nut and taurine, said Nicholas Connors, a medical toxicologist in the Division of Emergency Medicine at the Medical University of South Carolina in Charleston.

A person’s size can help determine how their body absorbs caffeine, so women can be more affected than men from the same cup of coffee. And the effects of caffeine can last for several hours, depending on the person’s daily level of consumption, Connors said.

“Used as most people use caffeine, it causes increased alertness, decreased fatigue and decreased appetite,” Connors said. “In overdose, it can cause seizures, agitation, fast heart rate and arrhythmias and nausea, vomiting and diarrhea.”

Though Watts did not call Cripe’s death a “caffeine overdose,” the teen’s father, Sean Cripe, warned against consuming too much caffeine and urged teens to stop buying energy drinks. Watts said Cripe was known to consume energy drinks, but his family did not consider his caffeine intake an addiction.

It’s unclear why Cripe drank so much caffeine in such a short amount of time, said Watts, who also ruled the teen had no “unfounded” or “undiagnosed heart condition.” But the combination of all three “was the perfect storm,” he said.

Watts said he understood the findings are “controversial” among those who dispute them. But he said he feels “very comfortable in what we have decided.”

“Caffeine, just like anything else, can be consumed in a fashion that can be dangerous,” Watts said. “I drink coffee. I drink soft drinks that have caffeine in them. But you need to be aware of the consequences of that stuff when taken in a short period of time.”

Kids, however, should never consume energy drinks, because its stimulants pose potential health risks, according to a report by the American Academy of Pediatrics.

This story was originally published May 16, 2017 at 5:49 PM with the headline "How does your daily dose of caffeine stack up?."