The Food and Drug Administration is investigating whether caffeine is an unsafe food additive to alcoholic drinks, with a decision to come as soon as this week, the Associated Press reported Tuesday.

U.S. Sen. Chuck Schumer (D-N.Y.), who has pushed the Obama administration to ban these beverages, says that a ban is imminent.

This decision would impact the sale of Four Loko, a drink that combines caffeine and alcohol and has recently gained popularity on college campuses, including at Washington University.

There is little scientific evidence to support that the drinks are less safe than other alcoholic drinks. But public health advocates, who support a ban on such drinks, say that the combination of caffeine and alcohol can make people feel more alert when intoxicated and more capable of handling dangerous tasks such as driving.

This fall, college students across the country have been hospitalized after drinking such beverages. A 23.5-ounce can of Four Loko costs about $2.50 and has an alcohol content of 12 percent—comparable to four beers.

At the state level, Washington, Michigan, Utah and Oklahoma have already banned the beverages.