Panera Bread is at the center of a newly filed lawsuit due to a controversial beverage sold at its cafés. NBC News reports that the lawsuit was filed on behalf of the family of a University of Pennsylvania student who died hours after drinking Panera's caffeinated Charged Lemonades.

The lawsuit, which was filed earlier this week in the Philadelphia Court of Common Pleas, describes the highly-caffeinated lemonade as "dangerous" and alleges that Panera doesn't properly warn customers about its ingredients.

This week's filing comes months after 21-year-old Sarah Katz bought a Charged Lemonade from a Panera location in Philadelphia and went into cardiac arrest after collapsing at a friend's birthday dinner. According to friends, Katz, who was diagnosed with the heart condition long QT syndrome at a young age, would have never purchased the beverage if she was aware of the caffeine content.

“She was very, very vigilant about what she needed to do to keep herself safe. I guarantee if Sarah had known how much caffeine this was, she never would have touched it with a 10-foot pole,” Victoria Rose Conroy, a close friend of Katz, shared with NBC News.

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Panera did offer a statement following the news of the lawsuit, letting it be known that they plan to investigate.

"We were very saddened to learn this morning about the tragic passing of Sarah Katz, and our hearts go out to her family. At Panera, we strongly believe in transparency around our ingredients. We will work quickly to thoroughly investigate this matter,” the statement read.

Panera's Charged Lemonades had a viral moment in December 20222 when a TikToker unexpectedly discovered that the beverage has more caffeine than four espresso shots.

According to the Panera website, a large serving of the Mango Yuzu Citrus or Strawberry Lemon Mint Charged Lemonade has 390 mg of caffeine, while a large Blood Orange (a sugar-free option) has 368 mg.

UPDATE: After the lawsuit was filed, the Food and Drug Administration announced on October 25 that it would be looking into the matter. “The FDA is saddened to hear of the passing of a consumer and as always, takes seriously reports of illnesses or injury from regulated products. At this point, we are gathering information about this event,” an FDA spokesperson said in a statement to NBC News. "The agency added that it 'monitors the marketplace of FDA-regulated products and takes action as appropriate, including collaborating with the Federal Trade Commission regarding marketing claims,'" NBC News reported.