Drugmakers are scrambling to pull Zantac off the shelves after a possible carcinogen was found in the heartburn med’s API. Now, a suite of federal lawsuits are claiming four companies declined to test their versions of the drug for the compound.

In a federal suit filed last week in California, attorneys for Walter Hantsen accused Sanofi, GlaxoSmithKline and Boehringer Ingelheim of misleading consumers about the dangers of generic and branded Zantac after they “deliberately crafted their label, marketing, and promotion” to downplay the potential health risks for patients.

A separate lawsuit in Colorado also pegged Pfizer as one of the defendants. A fifth company, Chattem, was also named in the suits.

“This was not done by accident or through some justifiable negligence,” Hantsen's attorneys wrote. “Rather, Defendants knew that it could turn a profit by convincing consumers that Zantac was harmless to humans, and that full disclosure of the true risks of Zantac would limit the amount of money Defendants would make selling Zantac.”

The lawsuits accused the drugmakers of being aware that a nitrosamine impurity called N-nitrosodimethylamine (NDMA) could be located in trace amounts in Zantac if proper testing was done, and of refusing to perform the proper testing each year.

Hantsen allegedly took a generic form of Zantac for nine years before being diagnosed with cancer, his attorneys wrote.

RELATED: Zantac maker Sanofi joins peers in recalling antacid

The French drugmaker said it continues to evaluate both the API of Zantac and its finished form and that it gets the API for the drugs sold inside and outside the U.S. and Canada from different sources. 

Sanofi’s move follows voluntary recalls of all unexpired products to the consumer level by a handful of drugmakers that manufacture generic Zantac. Novartis was the first to act, pulling its products as soon as the FDA warned of the risk of NDMA in the products. Dr. Reddy’s Laboratories and Apotex also began recalling drugs. Since then, the FDA has said early tests have found “unacceptable levels" of NDMA in samples of ranitidine.

GlaxoSmithKline and Teva, neither of which sell Zantac versions in the U.S., said they would voluntarily recall at least some of their products from other markets. 

The recalls have become somewhat superfluous in the U.S., as the largest pharmacy retailers—CVS, Rite Aid, Walmart and Walgreens—have announced they will temporarily quit selling the products and remove them from their shelves.