The caffeine-loaded “energy drinks” that are marketed to teenagers certainly provide a massive jolt for the companies that make them, with last year’s sales of $9 billion projected to more than double next year. That makes it all the more important for the Food and Drug Administration to regulate them, as evidence suggests that the jolt from these products may be too great for some growing bodies.

The number of people going to emergency rooms for energy drink-related visits has exploded 10-fold since 2005, to more than 13,000 in 2009. This fall, the FDA has listed 18 deaths in which consumption of drinks like 5-hour Energy and Monster Energy may have been a contributing cause. In many cases, consumers have no idea how much caffeine they’re guzzling because more than half of the 27 top-selling brands tested by Consumer Reports either do not list the amount of caffeine or contain much more than listed. While a 16-ounce Starbucks coffee contains 330 milligrams of caffeine, Consumer Reports found 242 milligrams in just 1.9 ounces of 5-hour Energy, and 229 milligrams in just 2.5 ounces of Rockstar Energy Shot. Manufacturers insist that most people take only a small serving, but anecdotal reports suggest that some young people chug serving after serving, hoping for a stronger buzz.