Some of Four Loko’s kick is getting the boot.

Federal officials said Wednesday that caffeine added to alcoholic malt beverages is “unsafe.” The Ohio Department of Commerce, Division of Liquor Control said the makers of Four Loko and Joose agreed to stop distributing their products in the state.

The Food and Drug Administration issued warning letters to four makers of caffeinated alcoholic beverages. The FDA said the companies’ drinks violate the Federal Food, Drug, and Cosmetic Act.

The letters gave recipients 15 days to reply with a plan of how to prevent a recurrence of the violation or a defense of their products.

Companies receiving such letters were Charge Beverages Corp., distributor of Core High Gravity drinks, New Century Brewing Co., distributor of Moonshot, United Brands Co. Inc., distributor of Joose and Max, and Phusion Projects, LLC, distributor of the college campus favorite, Four Loko.

Phusion Products said Tuesday they were removing caffeine, guarana, and taurine and will produce only non-caffeinated versions of Four Loko.

“There is evidence that the combinations of caffeine and alcohol in these products pose a public health concern,” said Dr. Joshua M. Sharfstein, Principal Deputy Commissioner of the FDA.

“While we don’t agree with the notion that mixing caffeine and alcohol is inherently unsafe, we do agree with the goal of keeping adults of legal age who choose to drink responsibly as safe and as informed as possible,” Phusion Products said in a press release.

Three Ohio State alumni founded Phusion Products.

Four Loko is sold in 23.5-ounce cans and contains 12 percent alcohol and as much caffeine as a 12-ounce coffee.