The Food and Drug Administration in May warned Americans to immediately stop using the over-the-counter diet drug Hydroxycut because of concerns over liver failure.

Yet the drug remains on store shelves in a new formulation, according to a report from CBS2Chicago.com.

The controversial supplement contains green tea and an African herbal supplement already banned in Europe, but not in the U.S.

After the recall, Americans from around the country who suffered liver damage from the product filed lawsuits against the company.

The product remains on the shelf and Hydroxycut said the FDA never concluded which ingrediant was causing the liver damage.

"No ingredient was identified as having a causal connection to liver concerns; nevertheless, out of an abundance of caution, all of the product's herbal ingredients and extracts have been replaced in the new formulation of Hydroxycut Advanced," said in a statement released earlier this month to New York's WCBS.

Flor Mendoza told CBS2Chicago.com she became sick while taking the drug.

"I felt nauseous and I felt tired," she said.

Mendoza is now has a new liver.

"A 31-year-old healthy woman, a mother of three children, who took Hydroxycut products for two and a half months, is in liver failure," said Mendoza's attorney Bob Kreisman.

Kreisman sued both the seller and manufacturer after doctors concluded Mendoza needed a new liver. She received a transplant several weeks later. Two other suits have been filed in Texas on behalf of users.

Click here to read more on this story from CBS2Chicago.com.