"I've been warning the e-cigarette industry for more than a year that they needed to do much more to stem the youth trends", Gottlieb said.
Of the 3.6 million middle- and high-school students who said they are tobacco-product users, 2.1 million used e-cigarettes, according to the Centers for Disease Control and Prevention.
"Juuling", along with "vaping", has become a common term for e-cigarette use by teenagers on social media and at US high schools.
Manufacturers offer and market e-cigarette flavors that clearly appeal to minors, including candy and bubble gum flavors. "These five brands now comprise over 97 percent of the US market for e-cigarettes", the FDA said.
The FDA said Wednesday that it has issued more than 1,300 warning letters and fines to retailers that illegally sold e-cigarette products to minors during a national sting operation at brick-and-mortar and online stores this summer.
Youth vaping is an "epidemic", as far as the FDA is concerned, and if manufacturers don't submit "robust" plans to prevent kids from getting their hands on flavored e-cigarettes, the agency will take action-possibly going so far as to order the flavored products off the shelves.
It marks a shift in the agency's tone on e-cigarettes.
San Francisco-based Juul, which commands over 60 percent of the e-cigarette market, said it is working to prevent underage use of its products but added that flavors can help adult smokers quit cigarettes.
Budding research on e-cigarettes also suggests that these flavors contain terpenes that may be more damaging to the lungs than other flavors are.
In a release, the FDA said it's taking "historic action" against companies that it believes promotes use and addiction of their products to young vapers.
If the plans fall short, the FDA could block sales of the products by enforcing a requirement that companies provide detailed design and health data about their products before marketing them.
But the FDA said it is also investigating whether e-cigarette manufacturers have introduced new products after August 8, 2016, without premarket authorization.
One manufacturer in the FDA's crosshairs, Juul Labs, said in a statement, "JUUL Labs will work proactively with FDA in response to its request". Gottlieb would be on much firmer ethical ground if he took the opposite position: In trying to stop teenagers from vaping, we won't deny adult smokers access to products that could save their lives.
"We're especially focused on the flavored e-cigarettes", said Gottlieb.
"We're announcing the largest ever coordinated initiative against violative sales in the history of the FDA". The agency issued 12 warning letters to companies that it says have deceptive marketing labels on e-liquids. The "epidemic" perceived by the FDA is mainly an epidemic of e-cigarette experimentation, and even that trend seems to have reversed, judging from the latest NYTS results.
To gain clearance to return to the market, the companies would have to prove that the benefits to adults who use e-cigarettes to stop smoking outweigh the risks associated with youth vaping.
On Wednesday, Gottlieb criticized e-cigarette companies' handling of the underage use problem, saying they approached it as "a public relations challenge rather than seriously considering their legal obligations".