Heartburn is bad enough. Making sense of your medication choices for gastroesophageal reflux disease (GERD) can make it even worse. Two of the most commonly prescribed proton pump inhibitors (PPIs) are omeprazole (Prilosec) and esomeprazole (Nexium). Both are now available as over-the-counter drugs. Take a closer look at both to see what benefits one medication may offer over the other.

Proton pumps are enzymes found in the parietal cells of your stomach. They make hydrochloric acid, the main ingredient of stomach acid.

Your body needs stomach acid for digestion. However, when the muscle between your stomach and esophagus doesn’t close properly, this acid can end up in your esophagus. This causes the burning feeling in your chest and throat associated with GERD. It can also cause asthma, coughing, and pneumonia.

PPIs decrease the amount of acid that is made by proton pumps. They work best when you take them an hour to 30 minutes before a meal. You’ll need to take them for several days before they’re fully effective.

PPIs have been in use since 1981. They’re considered the most effective medication for reducing stomach acid.

PPIs like Nexium and Prilosec are used to treat gastric acid-related conditions, including:

  • GERD
  • heartburn
  • esophagitis, or inflammation or erosion of the esophagus
  • stomach and duodenal ulcers caused by Helicobacter pylori infection or nonsteroidal anti-inflammatory drugs (NSAIDs)
  • Zollinger-Ellison syndrome, a disease in which tumors cause the production of excessive stomach acid

Omeprazole (Prilosec) and esomeprazole (Nexium) are chemically similar. However, there are minor differences.

Some studies indicate that the differences between the two drugs may offer some advantages to people with certain conditions.

A study published in Digestive Diseases and Sciences found that esomeprazole provided more effective control of GERD than omeprazole at the same doses. According to a study published in World Journal of Gastroenterology, esomeprazole offered faster relief than omeprazole in the first week of use. After one week, symptom relief was similar.

However, in an article in American Family Physician, doctors questioned these and other studies on PPIs. They cited concerns such as:

  • differences in the amount of active ingredients given in the studies
  • the size of the studies
  • the clinical methods used to measure effectiveness

The authors analyzed 41 studies on the effectiveness of PPIs. They concluded there is little difference in the effectiveness of PPIs.

The price of relief

The review of PPIs concluded that the biggest difference between Prilosec and Nexium was price. Until March 2014, Nexium was available only by prescription and at a significantly higher price. Nexium now offers an over-the-counter (OTC) product that’s priced competitively with Prilosec OTC. However, generic omeprazole may be less expensive than Prilosec OTC.

Traditionally, insurance companies did not cover over-the-counter products. However, the PPI market has led many to revise their coverage of Prilosec OTC and Nexium OTC. If your insurance still doesn’t cover over-the-counter PPIs, a prescription for generic omeprazole or esomeprazole may be your best option.

Most people don’t have side effects from PPIs. Infrequently, people may experience:

  • diarrhea
  • nausea
  • vomiting
  • headache

These side effects may be more likely with esomeprazole than omeprazole.

It’s also believed that both of these PPIs may increase the risk of:

  • spine and wrist fractures in postmenopausal women, especially if the medications are taken for a year or more or at higher doses
  • bacterial inflammation of the colon, especially after hospitalization
  • pneumonia
  • nutritional deficiencies, including vitamin B-12 and magnesium deficiencies

Many people experience excess acid production when they stop using PPIs. However, why this happens isn’t completely understood. It’s recommended that you taper off of the medication gradually.

Before taking either medication, tell your doctor if you:

  • are of Asian descent, as your body may take longer to process PPIs and you may need a different dosage
  • have liver disease
  • have had low magnesium levels
  • are pregnant or plan to become pregnant
  • are breastfeeding

Drug interactions

Always tell your doctor about all the drugs, herbs, and vitamins you take. Prilosec and Nexium can interact with other medications you might be taking.

The U.S. Food and Drug Administration (FDA) has issued a warning that the drug in Prilosec reduces the effectiveness of the blood thinner clopidogrel (Plavix). You should not take the two drugs together. Other PPIs are not included in the warning because they have not been tested for this action.

These drugs should not be taken with either Nexium or Prilosec:

Other drugs can interact with Nexium or Prilosec, but may still be taken with either drug. Tell your doctor if you take any of these drugs:

Generally, you can choose the PPI that’s readily available and costs less. But keep in mind that PPIs treat only the symptoms of GERD and other disorders. They don’t treat the cause. Lifestyle changes should be your first steps in controlling GERD and heartburn. Try weight management, avoiding big meals right before sleep, and quitting or refraining from tobacco use.