When consumers purchase over-the-counter medications at their local drugstore or grocery retailer, they tend to think the medication is relatively safe since it does not require a prescription.

However, as research continues on the side effects of over-the-counter and prescription drugs, new information comes to light that challenges that perception.

In particular, heartburn medication purchased over-the-counter is a very common occurrence.

Medications like Prilosec, Nexium and Prevacid were once available by prescription only, but then were released as over-the-counter medications available directly to the public without a doctor’s recommendation.

These three medications belong to a class of drugs known as proton pump inhibitors, or PPIs. They are designed to treat symptoms of heartburn and acid reflux by blocking the amount of acid the stomach produces.

In 2015, more than 15 million Americans used proton pump inhibitors to treat their heartburn.

As with any drug, both by prescription or as sold over-the-counter, side effects are common.

Minor side effects of over-the-counter heartburn medications include:

• Headache
• Diarrhea
• Constipation
• Flatulence
• Nausea
• Rash

Major side effects of over-the-counter heartburn medications include:

• Clostridium difficile infection
• Fractures of hip, wrist or spine due to osteoporosis
• Reduced absorption of vitamin B12
• Hypomagnesemia (reduced magnesium levels)
• Kidney problems
• Pneumonia

Latest Research on Major Side Effects of Heartburn Medication

New research into these drugs has found that users of PPIs experience a risk of chronic kidney problems that is 20 to 50% higher than those who do not use the drugs.

This particular study was published in the January edition of JAMA Internal Medicine, and while it does not establish a direct cause-and-effect relationship between kidney damage and heartburn medication, the researchers concluded, “We found there was an increasing risk associated with an increasing dose. That suggests that perhaps this observed effect is real.”

Prior research has found that using prescription heartburn medication has been linked with short-term kidney problems including inflammatory kidney disease, also called acute interstitial nephritis, and acute kidney injury.

The more recent research shows that these issues are not simply acute, but can also be chronic in nature. Chronic kidney damage can lead to kidney failure, requiring dialysis or kidney transplants, and the condition can be fatal.

It is not certain how PPI medications damage kidneys, but researchers currently have a few theories about the issue.

Some researchers believe magnesium levels due to heartburn medication use may directly lead to kidney injury. Others think that kidney problems may occur long term if patients have repeated issues of acute kidney inflammation due to the drugs.

It is important to note that there are other types of heartburn medication, and one of the common types is called an H2 blocker. Zantac, Pepcid and Tagamet are drugs in this class that are commonly used as an over-the-counter heartburn medication.

The research specifically looked at the differences in patients who had taken the PPI medications for heartburn versus those who had taken the H2 blocker medications to treat their heartburn, and found that the PPI users experienced a 39% higher risk of encountering kidney problems.

The researchers concluded that patients should talk to their doctors if they are using over-the-counter heartburn medication pills to treat their symptoms.