Link. Studies have shown almost 30 percent of college students consume energy drinks regularly … high concentrations of caffeine they contain can produce cardiovascular complications…

… The amount of caffeine differs widely among drinks but can range from about 80 milligrams to more than 500 milligrams. By comparison, a 12-ounce cola contains about 50 milligrams of caffeine, while a 5-ounce coffee has about 100 milligrams….

Presumably paroxysmal supraventricular tachycardia in young people who don’t routinely drink coffee.