According to allegations raised in a product liability lawsuit filed by a Florida man, side effects of Zantac have poisoned American consumers with high levels of the cancer-causing chemical NDMA for more than 35 years.

In a complaint (PDF) filed last week in the U.S. District Court for the Northern District of Florida, Philip McDonald indicates that he developed stomach cancer following use of Zantac, which resulted in the need for several rounds of chemotherapy and surgery.

The lawsuit seeks damages from Sanofi, Boehringer Ingelheim and GlaxoSmithKline, who manufactured and sold versions of Zantac or generic equivalents containing the pharmaceutical ingredient ranitidine, which has recently been found to break down inside the body, resulting in the known carcinogen N-Nitrosodimethylamine (NDMA).

According to allegations raised in the lawsuit, the manufacturers knew or should have known Zantac was poisoning users of the heartburn drug since the early 1980s, when the medication was first introduced.

“When laboratory researchers want to study tumors in experimental animals, the toxin of choice to induce tumors in experimental animals is often N-Nitrosodimethylamine,” McDonald notes in the lawsuit. “Unfortunately, the manufacturers of Zantac have been poisoning American consumers with extremely high levels of NDMA for over 35 years.”

McDonald indicates he took Zantac for six years, before he was diagnosed with stomach cancer in June. He indicates that the cancer was caused by NDMA in Zantac, and that if the manufacturers had warned himself and other consumers about the risk, they would not have taken the drug and would have used an alternative treatment for heartburn.

The case comes after a number of drug makers have issued Zantac recalls in recent months, removing ranitidine-containing drugs from the market due to the risk of NDMA poisoning.

Zantac (ranitidine) has been widely used by millions of Americans for treatment of heart burn and acid reflux. However, independent testing recently discovered that each pill contains levels of NDMA that far exceed the permissible daily intake levels set by the FDA.

NDMA is a chemical byproduct, which has been linked to reports of kidney cancer, stomach cancer, bladder cancer, small intestine cancer, liver cancer and other digestive tract cancers when contaminating other medications.

While the FDA’s permissible daily intake limit for NDMA is 96 ng, the online pharmacy Valisure recently determined that some Zantac tablets contain up to 3,000,000 ng of NDMA; 29,000 times the daily limit.

In September, Valisure filed a Citizens Petition, which calls for the drug to be recalled from the market, leading the FDA has issued warnings about the potential risk of Zantac NDMA contamination, which the agency is continuing to investigate.

As lawyers continue to investigate potential Zantac cancer claims over the coming months and years, it is widely expected that hundreds, if not thousands, of lawsuits similar to the one brought by McDonald may be filed against manufacturers of the drugs.

Tags: Boehringer Ingelheim, Cancer, GlaxoSmithKline, Heartburn, Heartburn Drug, NDMA, Sanofi, Stomach Cancer, Zantac