Home Proton Pump Inhibitors Prilosec Does Prilosec Cause Cancer?

Does Prilosec Cause Cancer?

Studies associate Prilosec with an increased risk of gastric cancer. Recent studies indicate a relationship between long-term use and higher incidence of cancer, even when controlling for confounding factors. Omeprazole, Prilosec’s active ingredient, also has links to other serious health issues.

Last Modified: November 7, 2023
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Does Omeprazole Cause Gastric Cancer?

Omeprazole, the primary ingredient in Prilosec, has an association with an increased risk of stomach cancer. A growing body of evidence also indicates a possible relationship between proton pump inhibitors such as Prilosec and gastric cancer.

PPIs inhibit gastric acid production, leading to an increase in the hormone gastrin. Several studies link higher gastrin levels with stomach cancer. Research findings indicate that people who take higher doses are more likely to develop cancer than those who don’t use PPIs. Patients diagnosed with acid reflux disease or other conditions that increase gastric cancer risks are even more susceptible.

“We found that PPI was associated with 82% increased risk of gastric cancer.”

A March 2023 systematic review found that long-term, or PPI use for more than one year, increased gastric cancer risks. Authors explained that as the time a person uses PPIs increases, so too does their “risk ratio.” Risk ratios reported in their findings were: 1.56 for less than one year of use; 1.75 for 1–3 years of use; and 2.32 for more than three years of use.

An increased risk of cancer isn’t listed among Prilosec side effects in package inserts. Some researchers note that unaccounted for variables may contribute to cancer formation. The 2023 systematic review, however, notes that even adjusting for these “confounding variables,” their analysis still found the risk of cancer increased with higher PPI dosages.

Some evidence suggests Prilosec use may increase the risk of pancreatic and esophageal cancers. Another 2023 systematic review, for example, states, “The findings of this updated meta-analysis demonstrate that the use of PPI was associated with an increased risk of pancreatic cancer.”

PPIs may also increase the risk of death from kidney and cardiovascular diseases. Other research suggests that PPI interactions with cancer drugs may inhibit their positive effects, most notably chemotherapy. This could increase the potential for disease progression.

Prilosec’s Relationship to Other Cancers
  • A meta-analysis of 11 studies found a 63% higher chance of pancreatic cancer, with the authors noting the potential for confounding factors and recommending further research.
  • Some recent research on esophageal cancer conflicts with one study indicating an increased likelihood, while another recommends using PPIs to prevent the disease in patients with the condition Barrett’s esophagus.
  • A University of Washington U.S. veterans cohort study found a higher mortality rate from kidney and cardiovascular diseases in those using PPIs.

A link between Prilosec and esophageal cancer is less clear, with conflicting research results. Some findings suggest the drug may prevent esophageal cancer in some instances. One study also suggests that PPIs may have an anti-cancer effect on breast cancer.

With mixed results and conflicting findings, more studies are needed. Researchers are exploring both possible benefits and possible life-threatening side effects of drugs containing omeprazole used for an extended period of time.

Mitigating Potential Risks

Most recommendations indicate limiting duration of PPI use is the best way to mitigate the potential risks. According to the U.S. Department of Veteran Affairs, ongoing acid suppression can lead to malabsorption of iron and vitamin B12, fractures, dementia, interstitial nephritis and end-stage renal disease.

The risk of side effects such as bone fractures and vitamin B12 deficiency occur after three months of use, while those taking the drug for more than three years are at an increased risk of stomach cancer. Anyone using Prilosec or other PPI drugs should discuss their concerns with their physician before altering their drug dosage.

Individuals who have experienced serious health injuries, including chronic kidney disease, end-stage renal failure and interstitial nephritis, have filed Prilosec lawsuits claiming manufacturer AstraZeneca knew of the risks but failed to warn consumers. However, to date, legal claims have yet to result in any Prilosec settlements.

How Can I Stop Using Prilosec?

Stopping the drug under a doctor’s guidance is often recommended. It’s often necessary to decrease the dosage over time to give the body time to adjust. Abruptly stopping all at once without replacing Prilosec can lead to increased stomach acidity. Even those who have made lifestyle changes may experience an acid rebound.

A physician might recommend drug alternatives to PPIs, such as H2 receptor antagonist drugs (e.g., Pepcid) and over-the-counter antacids (e.g., Maalox). Discontinuing Prilosec use — even when substituting a non-PPI drug — is often most successful when combined with lifestyle changes.

Commonly Recommended Lifestyle Changes
  • Eat acid-reducing foods: Low-acid and acid-reducing foods include whole grains, green vegetables, cruciferous vegetables, bananas, melons and nuts
  • Avoid highly acidic foods: Acid-inducing or highly acidic foods and drinks, include alcohol, dairy, processed foods, fried foods, caffeinated and carbonated drinks, animal fat, and citrus fruits and fruit drinks
  • Exercise: Engaging in a regular exercise regimen, including aerobic exercises
  • Complementary practices: Deep breathing techniques, meditation and weekly acupuncture may potentially be beneficial

Making lifestyle changes may reduce the need for drug therapy to treat acid reflux and heartburn. Patients may find it easier to discontinue Prilosec when engaging in healthy habits. A doctor may work with a dietician or nutritionist to develop a plan to reduce PPI intake while building lifestyle habits that decrease the need for it.

Please seek the advice of a medical professional before making health care decisions.