According to a recent study on contaminated medications, several batches of the blood pressure drug valsartan may have been contaminated with NDMA, an impurity that may put patients at risk for esophageal cancer.

What is Valsartan?

Valsartan is a medication for the treatment and prevention of high blood pressure and heart failure. About 3 million Americans take valsartan.

Valsartan is also known by its brand name, Diovan. It is in a category of drugs called angiotensin receptor blockers. These drugs work to reduce blood pressure by reducing the body’s reception for a chemical that causes blood vessels to narrow. This dilation of the blood vessels can help reduce blood pressure. In turn, this lowered blood pressure is supposed to help reduce a patient’s risk of congestive heart failure.

The drug was approved by the U.S. Food and Drug Administration (FDA) in December 1996 for use in both adults and children over the age of six.

Though it’s used broadly in the realm of blood pressure reduction and heart failure prevention, it can also be prescribed as a treatment after a heart attack. In the case of patients who have already suffered a heart attack, valsartan may help reduce a patient’s risk of dying from heart failure that sometimes follows a heart attack, when the heart muscles are weak.

Valsartan can also benefit patients who have already suffered congestive heart failure, says Medicine Net. In the case of these patients, the use of valsartan may help these patients avoid hospitalization.

Other than concerns about putting patients at risk for esophageal cancer because of its alleged NDMA contamination, valsartan is reportedly tolerated well by most patients, without many serious side effects. However, as with most medications, there are still some side effects. In the case of valsartan, these can include headache, fatigue, dizziness, nausea, abdominal pain, and a cough. If serious side effects occur, they may present in the form of an allergic reaction, impaired kidney function, impotence, and hyperkalemia (high potassium levels).

What is NDMA?

In May 2018, the possibly dangerous impurity N-nitrosodimethylamine (NDMA) was discovered in valsartan drugs made by Chinese manufacturer Zhejiang Huahai Pharmaceuticals. NDMA is a toxic chemical that has been classified by healthcare officials as a probable human carcinogen and may put patients at risk for esophageal cancer and numerous other cancers.

Due to these health risks, the FDA requested that three valsartan manufacturers voluntarily recall the tainted medication from the market.

In addition to being found as a contaminant in some medications including valsartan, NDMA can also be found in foods, such as grilled or smoked meats, fish, cheese, beer, tobacco, canned fruit, and some toiletries including shampoo. While NDMA is often only found in low levels in these products, any exposure to the substance may place consumers at higher risk for esophageal cancer or other health conditions.

How did the Contamination Happen?

There are two theories as to how valsartan and other medications became contaminated with NDMA.

The NDMA impurity in valsartan is suspected to be caused by changes in the manufacturing process at Zhejiang Huahai Pharmaceuticals. These changes were instituted in 2012, which may mean that tainted medication has been manufactured and distributed for years.

Although the FDA used to have a policy to inspect all foreign and domestic drug manufacturers every two years, this policy was changed in order to allow the administration to focus on inspections at factories that may be most likely to have issues. Due to this policy change, in 2017 it was discovered that approximately 1,000 drug factories had never been inspected by the administration.

Investigations and inspections that have occurred at overseas factories where valsartan and other tainted medications are manufactured have discovered many problems. Some factories have been found to have broken, dirty, or ancient machinery. In some cases, it has been found that drug anomalies have not been investigated or reported by manufacturers, and testing that turned up anomalies was either not reported, or falsified. At one factory that was inspected, employees were discovered destroying records.

The contamination may also be caused by a breakdown of the drug itself. Due to temperature changes and time, some medications may begin to break down into NDMA or other contaminants.

Are Valsartan Patients at Risk for Esophageal Cancer?

While all of the side effects of NDMA are not yet known, the chemical has been found to cause cancer, tumors, liver damage, and internal bleeding in animals. In humans, the chemical is suspected to cause cancer and may result in tumors on the esophagus and other internal areas of the body. A study published in Occupational and Environmental Medicine found a link between exposure to NDMA and an increased risk of esophageal cancer, oral cavity cancer, and pharynx cancer. 

What Are the Side Effects of NDMA?

In addition to potentially putting patients at risk for esophageal cancer, exposure to high levels of NDMA may also result in several side effects, including:

• 

  Headache

• Fever
• Nausea
• Vomiting
• Abdominal cramps
• Enlarged liver
• Dizziness
• Jaundice
• Liver, kidney, and lung damage

What Valsartan is Affected?

The valsartan included in the recall includes valsartan and valsartan hydrochlorothiazide distributed by several companies, including Major Pharmaceuticals, Solco Healthcare, and Teva Pharmaceuticals Industries. Not all drugs were included in the recall.

In an effort to assess the risk for patients, the FDA is continuing to test and review NDMA levels in valsartan drugs.The batch numbers and more information about the recall can be found through the FDA’s recall announcement.

Who May Be Affected By the Contaminated Batches?

According to the FDA, approximately one in 8,000 people who took contaminated valsartan may develop cancer due to the impurity. As the contamination may have begun as early as 2012, it’s possible that countless patients received tainted valsartan medication.

People who have been diagnosed with certain cancers due to the contaminated drugs may qualify to seek compensation from the manufacturer. Those who have been diagnosed with esophageal, intestinal, kidney, liver, pancreatic, prostate, or stomach, or colorectal cancer after taking valsartan in 2015 or later may be able to pursue compensation for their injuries, medical expenses, pain and suffering, loss of income or earning capacity, and other damages.