Medicines that may contain carcinogens

It is essential to appreciate that medications can improve health and some can even be life saving.  However, we must recall that they are in fact foreign chemicals that may present problems.  Recently, the FDA has warned that certain manufacturing lots of several very important medicines have been recalled because they have been found to contain higher than acceptable levels of chemicals known to cause cancer in animals.  These chemicals, known as nitrosamines, are a family of chemicals that are widely found in our environment and, when these are present at high levels and under conditions of prolonged exposure, they have been found to cause cancer in animals and are therefore suspected to possibly cause cancer in humans.

Very low levels of nitrosamines are considered to be safe and can be found in our drinking water and foods, especially charred or grilled foods.  For this reason, ingestion of large quantities of flame grilled, charred foods is discouraged by nutrition experts.

One of these nitroso chemicals, nitrosodimethylamine or NDMA, has been classified by the Environmental Protection Agency and the World Health Organization as a “probable carcinogen.”  The FDA has required testing of all medications for the presence of NDMA and has recently asked drug makers to recall lots of certain medicines that were found to have unacceptably high levels of the chemical.  The medicines that have been recalled are certain specific lots of drugs taken for high blood pressure (valsartan, losartan, irbesartan), a stomach acid blocker (ranitidine), a smoking cessation drug (varenicline) and a diabetic drug (metformin).  Importantly, many lots of these drugs do not contain excessive levels of NDMA.  

What should you do?

1. If you are taking one of the medicines listed above, don’t stop taking your medicine before checking with your doctor.
2. Check with your pharmacist and see if your medication has been recalled.
3. Do not discard this medicine or any prescription medicine down the drain where it would enter our aquifer (water supply).
4. Find a medication take-back program such as your county health department’s Dispose-A-Med program and discard these and any medications that you are no longer taking. 

Taking any medication safely requires that we become fully informed and get the very best effects from our medicines and none of the potential harm. 

Raymond L. Woosley, MD, PhD

AZCERT