The U. S. Food and Drug Administration (FDA) has stepped up its search for medications that contain probable human carcinogens known as nitrosamine after pulling the popular heartburn drug Zantac (ranitidine) off the market in April when it found levels of the nitrosamine NDMA (N-nitrosodimethylamine) increased in the medication over time. The impurity has also been spotted in several extended-release versions of the diabetes drug metformin as well as the blood pressure medication valsartan and other ARBs, prompting numerous recalls. And now nitrosamine has turned up at unsafe levels in two tuberculosis drugs.
But this time the FDA isn’t demanding a recall, in order to “maintain patient access to these life-saving medications.”
“To mitigate or avoid shortages and to help ensure patients have access to these necessary medicines, FDA will not object to certain manufacturers temporarily distributing rifampin containing 1-methyl-4-nitrosopiperazine (MNP) or rifapentine containing 1-cyclopentyl-4-nitrosopiperazine (CPNP) above the acceptable intake limits until they can reduce or eliminate the impurities,” the agency said in a news release. MNP and CPNP are two other nitrosamine compounds.
The FDA is investigating how the impurity turned up in the tuberculosis meds and is developing testing methods to better identify MNP and CPNP.
Nitrosamines are chemical compounds present in some foods and drinking water supplies. The FDA sets limits to determine what is considered safe daily limits of the nitrosamines based on lifetime consumption. For NDMA, levels above 96 nanograms are considered unsafe. For MNP, levels should not exceed 0.16 parts per million (ppm), and for CPNA, levels should not exceed 0.1 ppm.
Attorneys with Beasley Allen Law Firm are currently investigating claims of those who have used Zantac, which was voluntarily recalled from the market on Sept. 13, 2019, and withdrawn on April 1, and has been linked to certain types of cancer, including liver, bladder, stomach, colon, kidney and pancreatic cancer. If you or a loved one was a regular user of Zantac or any other product containing ranitidine and have been diagnosed with cancer, we would like to talk with you. Contact Frank Woodson, one of our leading pharmaceutical attorneys in charge of Zantac cancer claims.