NEW YORK (AP) -- Monster Beverage is suing San Francisco's city attorney over demands that the energy drink maker reduce the amount of caffeine in its drinks and change its marketing practices.
The company, based in Corona, Calif., says it's being unfairly singled out by City Attorney Dennis Herrera, who late last year had asked Monster to produce documentation showing that its drinks are safe. Since then, Monster says Herrera has asked it to reformulate its drinks and change its labels and marketing materials.
A representative for the city attorney's office did not immediately return a call for comment.
The suit comes at a time when the energy drink industry has come under intense scrutiny. The Food and Drug Administration is investigating reports of deaths linked to energy drinks, although the agency has noted that the reports don't prove the drinks caused the deaths.
New York's attorney general has also subpoenaed Monster — as well as the maker of 5-Hour Energy shots and PepsiCo Inc., which makes Amp — as part of an investigation into how energy drinks are made and marketed. In addition, the family of a 14-year-old girl is suing Monster after they said she died after drinking two 24-ounce cans of Monster in a short period.
Monster has stood by the safety of its drinks. Earlier this year, the company hit back at the lawsuit and said there was no blood test performed to confirm that the girl died of caffeine toxicity.
In its lawsuit against San Francisco's city attorney, Monster Beverage Corp. notes that "any child can walk into a Starbucks and buy an unlimited number" of 16-ounce brewed coffees, which Monster says have twice as much caffeine as its energy drinks.
The lawsuit cited a letter from Herrera dated March 29 asking Monster to provide "adequate warning labels" and to stop targeting minors in marketing materials.
Monster's current label says drinkers should limit themselves to one can every four hours and a maximum of three per day. It also says the drink isn't recommended for children, people sensitive to caffeine, pregnant women or women who are nursing.
The city attorney said in his letter that three cans amount to 480 milligrams of caffeine, nearly five times the recommended maximum for adolescents and above the 400 milligrams per day the FDA has indicated is safe for adults.
The suit was filed in the U.S. District Court, Central District of California.
Even as soda consumption has flagged in recent years, energy drinks including Red Bull and Rockstar have surged in popularity. In 2011, sales volume for energy drinks rose by nearly 17 percent, according to Beverage Digest, an industry tracker.