CHICAGO (CBS) — A family is suing the Chicago-based maker of a fruit-flavored alcoholic beverage, following the death of their teenager who drank what the attorneys call “blackout in a can” before a concert.

The lawsuit was filed in Cook County against Phusion Projects’ Four Loko, which attorneys say is heavily marketed to young people.

The family of 15-year-old Bo Rupp, who died after ingesting two cans of the beverage, wants to raise awareness of the product as the prom and graduation party season kicks in, according to a news release issued by the attorneys in the case.

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Rupp’s parents, John and Karla, charge in the suit that Phusion Projects “was careless and negligent in formulating a caffeinated, alcoholic beverage that desensitizes users to the symptoms of intoxication, and increases the potential for alcohol-related harm.”

The lawsuit contends that one 23-ounce can of Four Loko has similar alcohol content to a six-pack of beer. It comes in a variety of fruit flavors that appeal to young people.

According to Four Loko’s website, the beverage is sold in 23.5-ounce cans with either 6 or 12 percent alcohol, depending on state regulations. Four Loko has roughly the same alcohol content as wine and some craft beers, and far less alcohol by volume than hard liquor, the company says.

Rupp, of suburban Washington, D.C., drank two cans of Four Loko, becoming highly intoxicated and then losing his life after he walked onto a roadway near his home last fall, according to the lawsuit.

At a news conference today, Karla Rupp, Bo’s mother, recalled the events of Sept. 25, 2010.

Bo Rupp drank the contents of two Four Lokos, which also included caffeine, in about an hour before a concert. When the concert staff noticed Bo’s behavior and that he appeared extremely intoxicated, they called his mother to retrieve him.

The beverage was purchased at a convenience store before the concert.

When Bo’s mother arrived, her son was paranoid and disoriented. When they arrived in their suburban neighborhood, Bo took off on foot. Although both of his parents urged him to come home via text messages, Bo’s responses were confusing.

“Eventually we lost all contact. Bo made his way on foot onto a busy road, and then he was hit by a car,” Karla Rupp said.

“I hope other parents will talk to their children about this drink,’’ she said. “We don’t want any other family to go through the sheer terror of losing a child.’’

“This was a boy who was raised by concerned parents, who had a stable home life and lots of friends,” said Jeffrey Simon of Simon, Eddins & Greenstone, LLP of Dallas, which is serving as co-counsel in the lawsuit. “What killed him was not the type of alcohol that adults might serve at a party. Four Loko is so deliberately different — it’s sweet and fruity and marketed directly at the underage crowd – that it is far more dangerous than other drinks. And the founders of Four Loko knew that from the beginning.”

Simon pointed out that if Rupp had overindulged on most any other alcoholic beverage that night, he probably would have vomited or passed out. But the stimulants in the drink are known to mask the effects of being drunk, and so even more experienced drinkers don’t realize they’re intoxicated.

In November, 2010 the makers of Four Loko agreed to remove caffeine from the drink.

“We are extremely saddened by this tragedy and our thoughts are with the Rupp family,” the company said in a statement. “This accident, and others like it, speak to the serious, societal concerns regarding the misuse of alcohol – alcohol abuse and underage drinking are problems we would all like to see discussed and solved.

“It is important to remember that because a complaint is filed, doesn’t mean the allegations in it have merit. We plan to defend this case in the courts rather than in the press, and we will do so vigorously.

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