Nexium (esomeprazole) is a member of a group of drugs called proton pump inhibitors (PPIs). Prilosec (also known as omeprazole), Prevacid (lansoprazole), Aciphex (rabeprazole) and Protonix (pantoprazole) and Nexium are used to reduce the amount of acid produced in the stomach. The PPIs are commonly used to treat the symptoms of gastroesophageal reflux disease (GERD). Drugs that block the H-2 receptor such as Tagamet (cimetidine), Zantac (ranitidine) and others also reduce stomach acid production and are commonly used to treat GERD.

Barrett's esophagus is a condition caused by chronic GERD. The cells at the bottom of the esophagus are damaged by the repeated reflux of stomach acid and turn into cells that are similar to those in the stomach lining. Unfortunately, these cells have a higher risk of becoming cancerous. Annually, about one in 200 people with Barrett's will develop cancer of the esophagus. Drugs are used to reduce or eliminate the amount of acid produced in the stomach and reduce damage to the esophagus. Control of stomach acid production has been done with the H-2 receptor blockers and PPIs.

Last year a study was published that noted an increased risk of community-acquired pneumonia in people being treated with acid-suppressing drugs including the PPIs. People taking PPIs appeared to have a doubled risk of developing pneumonia. The risk is presumably due to the decrease in acid in the stomach. The risk of pneumonia is about one person in 200 taking PPIs for a year. The risk was a bit lower in people taking H-2 receptor blockers, but that may be because these drugs are not as good at reducing stomach acid. Although the risk is increased, the relative risk for any person taking PPIs is still very low.

The risks of pneumonia need to be balanced against the risk of developing cancer of the esophagus. Although the risk of pneumonia is just about the same as the risk of developing cancer of the esophagus, pneumonia can be treated with effective antibiotics. Cancer of the esophagus treatment involves surgery, radiation and chemotherapy. Because it is usually diagnosed late, cancer of the esophagus is not normally curable.