An e-cigarette that looks like a flash drive is gaining popularity among teenagers and can serve as a gateway to nicotine addiction.

A JUUL is a battery-powered e-cigarette that works by heating liquid into a vapor the user can inhale. The product is meant to appeal to young people.

“Teens are enticed to try JUUL because of its flavorings,” says Sarah Garwood, MD, a Washington University adolescent medicine physician at St. Louis Children’s Hospital. “The JUUL may have a certain ‘cool’ factor due to its design and the fact that it can pass for something harmless, like a thumb drive.”

Juuling, however, is anything but harmless. The vapor contains a variety of chemicals, including more than double the concentration of nicotine as other e-cigarettes, according to the American Academy of Pediatrics.

“E-cigarettes are not safe,” says Thomas Ferkol, MD, a Washington University pediatric pulmonologist at St. Louis Children’s Hospital. “We’re still learning how harmful they are. These products are leading to new generations becoming addicted to nicotine.”

Need resources for your teen? Call 314.454.TEEN, a free helpline for parents of teens.