By the Way, Doctor: Is it safe to take Prilosec long-term?

Q I’ve been taking Prilosec for esophageal reflux. My doctor says I may need to take it indefinitely. Is that safe?

A Prilosec (generic name omeprazole) is a member of a class of drugs called proton pump inhibitors (PPIs) that has revolutionized the treatment of gastroesophageal reflux disease (GERD). PPIs work by shutting down the "proton pump," an enzyme involved in the production of stomach acid. Although acid is necessary for digestion, acidic stomach contents can damage the esophagus, the tube that carries food from the mouth to the stomach.

GERD occurs when the lower esophageal sphincter (a valvelike muscle at the bottom of the esophagus) fails to close properly, and stomach contents flow back or "reflux" into the esophagus. When refluxed stomach acid strikes the esophagus, it causes the burning sensation, better known as "heartburn," that you feel in your chest and throat.

Prilosec and other PPIs — esomeprazole (Nexium), lansoprazole (Prevacid), pantoprazole (Protonix), and rabeprazole (Aciphex) — are the most effective drugs for treating GERD. Since the condition is chronic, many people will need to take a PPI indefinitely because symptoms often return if they stop.

Since PPIs have only been in widespread use since the 1990s, we don’t have much information about their long-term effects. Studies of patients taking omeprazole for up to 15 years have shown no significant adverse effects. Biopsies of stomach tissue have shown increases in certain kinds of cells and in stomach polyps, but neither of these changes is considered dangerous.

Even when drugs control their symptoms, anyone with GERD should be regularly checked for complications of the condition, such as bleeding or ulcers in the esophagus. Also, scarring can narrow the esophagus and make swallowing difficult. Some people with GERD develop Barrett’s esophagus, a condition in which the cells lining the esophagus change and, over time, become cancerous.

Proton pump inhibitors are most effective when taken before a meal. Although PPIs have few drug interactions, if you’re taking other medications, you should check with your pharmacist or doctor to be sure.

— Celeste Robb-Nicholson, M.D.Editor in Chief, HWHW