(KMOV) -- Tiny energy drinks can pack some serious health risks. The drinks are popular with younger consumers, like teenagers, but can be very dangerous, according to health care professionals.
Because of the risk, one St. Louis area chain store is restricting the sale of energy shots to minors.
Casey's General Store requires identification from customers who want to buy energy shots, like 5-hour Energy or 8-Hour Buzz.
John Reynolds, of Alton, Illinois, says Casey's is doing the right thing.
"I definitely think minors shouldn't be able to buy them. They're not right."
Reynolds' teenage son used to drink several energy drinks at a time.
"I said how many are you drinking and he said four or five. And I said you can't do that."
Doctors say the drinks can be dangerous even for perfectly healthy adults. Some of them have more than four times the amount of caffeine than what is found in a cup of coffee.
"A cup of coffee contains about 85 milligrams of caffeine per cup, these drinks can contain up to 400 milligrams of caffeine per serving," said Dr. Ali Zaiee, a cardiologist with SSM.
Dr. Zaiee says energy shots can put extreme stress on the cardiovascular system.
"The heart is almost like a car engine and when a car is going 100-120 miles per hour for a significant amount of time, that engine can wear out. And this is what those energy drinks are doing," Dr. Zaiee said.
News Four found other gas stations that also require ID before purchasing energy shots. There is no Missouri law restricting the age of consumers of the drinks.