The Food and Drug Administration said Breathable Foods Inc labeled AeroShot as both inhaled and ingestible, which is contradictory and could be unsafe.

The warning letter posted online Tuesday by the FDA comes after U.S. Sen. Charles Schumer urged the agency to review the safety and legality of the breathable caffeine.

"Caffeine is not normally inhaled into the lungs and the safety of doing so has not been well studied," the FDA said in a news release. While the company said AeroShot particles are too big to enter the lungs, it did not have research to back up its claim, the FDA said.

Breathable Foods, based in Cambridge, Massachusetts, launched AeroShot Pure Energy in the United States earlier this year as a calorie-free breathable energy product that "delivers an airborne shot of caffeine through a pocket-sized, single-use device." It recommends a sales price of $2.99.

The gray and fluorescent yellow dispenser looks a cross between a lipstick and a shotgun shell.

Each shot delivers a blend of caffeine and B vitamins in a fine powder that quickly dissolves in the mouth, the company said. One AeroShot contains four to six puffs for a combined total of 100 milligrams of caffeine, about the same amount as a large cup of coffee.

The FDA has come under fire from consumer groups and lawmakers for not doing enough to help consumers navigate the conflicting claims of dietary supplements. The Government Accountability Office has also said the FDA needs more power to regulate supplements.

The agency also warned that AeroShot's label does not include a telephone number for reporting complaints, and has conflicting statements about whether it is appropriate for those under the age of 18. The FDA said it has not received any complaints about AeroShot so far.

Also, some videos on the company's website seem to encourage people to use AeroShot with alcohol as a "party drug," the FDA said in its letter, dated March 5. AeroShot's inventor, David Edwards, states in another video that the product should not be used with alcohol.

In response to the FDA, Breathable Foods said the product is not recommended for people under 18 years of age, or for use with alcohol, and is also ingested, not inhaled.

"We plan to work closely with the FDA to meet their requests for information and labeling changes to ensure compliance with dietary supplement requirements," Breathable Foods Chief Executive Tom Hadfield said in a statement.

The FDA asked Breathable Foods to correct the violations and provide more information on research. The company has 15 business days to respond to the letter.

"This stern warning is the clearest indication yet that AeroShot needs to be taken off the market until these concerns can be addressed and the product's safety can be confirmed," Senator Schumer said in a statement, adding that he warned the FDA about the product in December.

(Reporting by Anna Yukhananov; Editing by Tim Dobbyn)

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