MONDAY, May 10, 2010 (Health.com) — Too many people in the U.S. may be taking stomach-acid-suppressing drugs such as Nexium and Prevacid, new research suggests. The drugs, known as proton pump inhibitors, help those with serious stomach and digestive problems, but the risks may outweigh the benefits for people with less serious conditions, experts say.
Proton pump inhibitors can have rare but serious side effects, including an increased risk of bacterial infection and bone fracture, according to several new studies in the Archives of Internal Medicine.
Proton pump inhibitors are among the most commonly prescribed drugs in the U.S. In 2009, they were the third-largest class of drug in the country with $13.6 billion in sales, representing more than 110 million prescriptions, according to IMS Health, a health-care market research firm.
Nexium and Prevacid (which is also available as a generic drug, lansoprazole) are the two most popular proton pump inhibitors, according to the most recent government data. Other drugs in the class include Prilosec, Zegerid, Protonix, and Aciphex.
“These medications definitely have benefits for a vast number of patients, but they also carry some really meaningful risks of diseases that can be catastrophic,” says Michael Howell, MD, the lead author of one of the studies and the director of critical-care quality at Beth Israel Deaconess Medical Center in Boston. “Every doctor should look at every patient and give them the lowest level of gastric acid suppression that they think is safe. For many patients, that would be none.”
Two of the new studies found that proton pump inhibitors are associated with an increased risk of infection from the bacterium Clostridium difficile, a hard-to-treat intestinal infection that can occur in people taking antibiotics. C. difficile typically results in severe diarrhea but can lead to removal of the colon or even death in extreme cases.
C. difficile can be picked up in hospitals, but stomach acid seems to protect against the bacteria. Taking acid-suppressing drugs may allow the bacteria to gain a foothold, which can result in infection. C. difficile infection “is an awful disease, and we felt we were seeing more of it,” says Dr. Howell.
In one of the studies, Dr. Howell and his colleagues examined data from more than 100,000 patients hospitalized for conditions ranging from cancer to dehydration. People who took a proton pump inhibitor once a day had a 74% increased risk of acquiring a C. difficile infection in the hospital, the researchers found, while people who took the drugs more frequently were at more than twice the risk of infection.
The overall risk was small, however. The rate of infection was 0.9% and 1.4% in those taking the drugs daily and more than once a day, respectively, compared to 0.3% in individuals who didn’t receive any acid-suppression therapy.
In another study, conducted by a separate research team, patients who were already being treated for C. difficile infections and took a proton pump inhibitor were 42% more likely to see the infection return compared to similar patients who didn’t take the drugs.
“There are benefits to using PPIs, but as we move forward I think we need to really look at the indications, given that there are benefits but also risks for each individual patient,” says Amy Linsky, MD, lead author of that study and a fellow in internal medicine at Boston Medical Center.
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