Updated

Federal regulators are expected to move to ban caffeinated alcoholic drinks as soon as this week, according to a New York senator.

Democratic Sen. Charles Schumer, who has pushed the Obama administration to ban the beverages, said Tuesday the Food and Drug Administration is expected to find that caffeine is an unsafe food additive to alcoholic drinks, essentially banning them.

The Federal Trade Commission will then issue letters to caffeinated alcoholic beverage manufacturers warning that marketing them could be illegal, he said.

"This ruling should be the nail in the coffin of these dangerous and toxic drinks," Schumer said.

College students have been hospitalized after drinking the beverages, including the popular Four Loko. Four states — Washington, Michigan, Utah and Oklahoma — have banned them and other states are considering similar action. Police in Mesa, Ariz., said an "extremely intoxicated" teenager smashed her SUV into a tree Sunday morning after reportedly playing "beer pong" with Four Loko.

A year ago, the FDA notified more than two dozen manufacturers of caffeinated alcoholic beverages that it has never specifically approved the addition of caffeine to alcoholic drinks and began studying whether it is unsafe and should be outlawed.

The agency noted the mix's growing popularity among college students and its potential health and safety issues. Officials noted a Wake Forest University study that students who combine caffeine and alcohol are more likely to suffer alcohol-related injuries than those drinking alcohol without caffeine.

Four Loko comes in several varieties, including fruit punch and blue raspberry. A 23.5-ounce can sells for about $2.50 and has an alcohol content of 12 percent, comparable to four beers, according to the company's website.

FDA spokeswoman Siobhan DeLancey would not confirm any upcoming action, but said the agency recognizes "this very important public health issue" and will announce the results of its review when it is complete. The FTC did not immediately respond to a request for comment.