They come in the smallest of bottles to the biggest of cans. Each promising to "keep you awake for hours." Yes, energy drinks are everywhere.
The sweet tasting beverages are now outselling bottled water, according to industry observers. Sales are up nearly 20 percent over the last 12 months.
Scientists fear that those sales numbers are propped up by teenagers who have come to rely on a burst of energy that comes in a can.
Many are using the drinks for a long night of studying or a boost before athletic practice or a big game.
Dr. Michael Burgeron, of Stanford University, is researching how energy drinks affect teenagers.
"A lot of kids are using the caffeine energy drinks to stay awake, more alert in school, probably very few to enhance athletic performance," he said.
In this month's journal of the Academy of Pediatrics, he offers his preliminary conclusion.
"There's no real good reason a child or adolescent should be consuming caffeine," he said.
Bergeron says it's the caffeine that separates energy drinks from sports drinks. Sports drinks can be beneficial during and after exercise because they contain carbohydrates and electrolytes. Energy drinks provide energy thanks to sugar and caffeine.
In fact, a 16-ounce can may contain up to 14 teaspoons of sugar and 200 milligrams of caffeine. That combination can elevate blood pressure, increase heart rate even slow brain function.
Bergeron said if they are using energy drinks for these purposes, "There's clearly a problem."
In Central Florida, the Lake County School District has banned energy drinks altogether. They can't be sold on campus or brought there from home.
Orange, Seminole, Volusia and Osceola school districts don't sell the drinks on campus but don't prevent students from bringing them to school.
Brevard County doesn't have an energy drink policy.
Psychologist Robert Boxley has seen the affects of energy drinks on teenagers. He offers this warning: "Once you get used to the idea that you put something in your body to change the way you feel, you open the door to all kinds of possibilities."
Energy drinks are considered dietary supplements and are therefore not regulated. While many have warnings advising children not to drink them, the law allows anyone to buy them.