Last week, a mother in Maryland sued the makers of caffeine-heavy Monster Energy drink, alleging that the beverage was not only behind the death of her teen daughter, but that the company knew of possible health risks and failed to warn consumers.

The 14-year-old died last December after consuming two 24-ounce Monster Energy cans within a 24-hour period. A lawyer for the late girl’s mother claims the cause of death was “caffeine toxicity in the setting of a cardiac arrhythmia.”

According to records uncovered by a Freedom of Information Act request filed by the plaintiff, the FDA has received 37 adverse incident reports allegedly related to Monster. A rep for the agency confirmed to reporters yesterday that five of those incidents involve deaths with a sixth, non-fatal heart attack also listed.

It’s not known what other factors — alcohol, drugs, etc. — might be involved in any of these incidents.

In a statement to Bloomberg, the company has denied any wrongdoing:

Over the past 16 years Monster has sold more than 8 billion energy drinks, which have been safely consumed worldwide… Monster does not believe that its beverages are in any way responsible for the death of [the 14-year-old]. Monster is unaware of any fatality anywhere that has been caused by its drinks.

While there are FDA guidelines for safe levels of caffeine in soda, most energy drinks aren’t subject to the same thresholds because they are marketed as dietary supplements. A typical 24-ounce Monster has around 240 mg of caffeine, or about 1.7 times the amount of caffeine a soda could have and still be considered safe by the FDA, but less than the approx. 330 mg. the FDA says you would get from a 16-ounce coffee.

Between 2005 and 2009, the number of emergency room visits tied to energy drinks increased tenfold.

Earlier this year, Illinois Senator Dick Durbin asked the FDA to consider caffeine limits on energy drinks and the agency has said it “continues to evaluate the emerging science on a variety of ingredients, including caffeine.”

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