Does Omeprazole Cause Cancer?

Prilosec (omeprazole) may cause cancer, with some studies finding an association between this proton pump inhibitor (PPI) and an increased risk of gastric (stomach) cancer.

PPIs are among the most commonly prescribed drugs in the United States. The emerging evidence from a number of studies implicates these medications when used over the long term to treat digestive disorders.

This article explains research to date on the link between PPIs and cancer, as well as alternatives to treatment with omeprazole.

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How Omeprazole Increases Cancer Risk

PPIs like omeprazole, rabeprazole, lansoprazole, and esomeprazole are used to treat helicobacter pylori (H. pylori) infection, acid reflux, and gastroesophageal reflux disease (GERD).

When digesting food, the stomach uses gastric acid to break food down. During this process, cells in the stomach called G cells produce a hormone called gastrin, which signals to other cells to pump acid. PPIs stop acid from being produced.

The body responds by recognizing there isn't enough acid and seeks to make more by producing more gastrin. Too much gastrin has been found to promote the growth of gastrointestinal tumors.

Some studies have suggested that gastric-acid suppression from PPIs leads to:

  • Elevated levels of gastrin
  • Inflammation of the stomach lining
  • Bacterial overgrowth

This in turn may play a role in the development of cancer in the gastrointestinal system.

A 2019 study found that even when H. pylori infection was eradicated, the long-term use of PPIs was still associated with a twofold increased risk for gastric cancer.

Other Risks From PPIs

Prolonged use of PPIs has been linked to:

Should I Stop Using Prilosec?

PPIs like Prilosec and Prevacid (lansoprazole) are available over the counter without a prescription. But long term use can be problematic, even at the lower doses.

The U.S. Food and Drug Administration (FDA) says over-the-counter (OTC) PPIs should only be taken for the 14-day course up to three times a year.

In some cases, other medications (like an H2 blocker) may be appropriate. However, some people may still experience difficult symptoms after coming off PPIs and may need to go back on them at a higher dosage.

Stopping PPIs Abruptly Could Cause Rebound Effects

If you have been taking PPIs for at least a few weeks, you should not stop taking the medication suddenly. Doing so may cause a rebound effect with stomach acid. People who take PPIs should discuss treatment options or changes with their healthcare provider.

Alternatives to PPIs

Although PPIs are commonly prescribed in the U.S., there are alternative options available. These can include lifestyle modifications, alternative therapies, and other medications.

Other Medications

There are other medications that can be used instead of PPIs in the treatment of conditions like acid reflux.

H2 blockers are medications that lower the production of hydrochloric acid in the stomach. They are absorbed quickly and the resulting acid suppression lasts for several hours after the medications have been taken. H2 blockers can also work to counter the effect of acid on the esophagus that causes heartburn.

H2 blockers include:

  • Tagamet (cimetidine)
  • Axid (nizatidine)
  • Pepcid (famotidine)

Antacids may be appropriate in some cases. These drugs work by neutralizing stomach acid. They are the oldest treatment for heartburn on the market. Most antacids are a mixture of aluminum and magnesium hydroxide. Some may also contain sodium bicarbonate.

Lifestyle Changes

As well as medications, lifestyle changes can in some cases assist with conditions treated by PPIs like acid reflux or GERD.

Lifestyle changes that may help include:

  • Losing weight
  • Quitting smoking
  • Eating smaller meals
  • Getting adequate sleep
  • Raising the head of the bed at night for sleep
  • Avoiding spicy, fatty, or acidic food and drinks, like citrus, chocolate, mints, coffee, alcohol, and tomato-based products

Alternative Therapy

Some alternative therapies that may be helpful as an alternative for PPIs include:

  • Acupuncture
  • Hypnotherapy
  • Herbal remedies

Herbal remedies that may be helpful include:

  • Chamomile: Chamomile tea can soothe the digestive tract, but shouldn't be taken by those who have a ragweed allergy.
  • Licorice: This is believed to help the coating of the esophagus to protect it from irritation due to stomach acid.
  • Ginger: This has been used for centuries to aid in digestion and as a remedy for heartburn.

How to Prevent Heartburn

There are a number of steps that may help you to avoid acid reflux or GERD, and that could limit the need for omeprazole and other PPI medications.

Some ways to prevent acid reflux or GERD in the first place include:

  • Maintaining a healthy weight: An increased weight can increase the risk of acid reflux and GERD. Losing weight if overweight can help avoid this, as can maintaining a healthy weight.
  • Don't smoke: Nicotine is the ingredient in tobacco that makes smoking addictive. It is believed nicotine also relaxes the esophageal sphincter which can lead to reflux or heartburn.
  • Avoid certain foods and drinks: As mentioned above, avoiding spicy, fatty, or triggering foods and drinks like tomatoes, mint, or coffee can help avoid reflux.
  • Avoid carbonated beverages: Bubbly drinks like soda and sparkling water can cause burping, which sends acid to the esophagus. Drinking flat drinks like water will help avoid this.
  • Stay upright after eating: Sitting upright or standing after eating helps keep acid in the stomach. Eating no later than three hours before going to bed will help avoid reflux.
  • Avoid speedy activity after eating: Vigorous exercise or workouts that involve bending over can cause acid to rise to the esophagus. Wait a couple of hours after eating before working out vigorously.
  • Sleep with your head elevated: When sleeping, your head should be six to eight inches higher than your feet. This can be achieved through a foam wedge to support the upper parts of the body or using bed risers on the legs of the bed near the head.

Some medicines can relax the esophageal sphincter, causing reflux. Others can irritate the esophagus. Always speak with your healthcare provider before discontinuing or changing any medications.

Summary

PPIs like omeprazole are used to treat GERD and acid reflux, but they may cause elevated gastrin levels in the stomach. This may play a role in the development of gastric cancer.

Long-term use of PPIs may cause certain health risks, but other medications and lifestyle changes may help manage these conditions. Prevention strategies like stopping smoking and changes in diet may help manage GERD to avoid the need for medication.

12 Sources
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