The Prilosec stomach cancer risk may make the anti-acid drug more trouble than its worth, according to recent studies.

Prilosec (omeprazole) is a proton pump inhibitor (PPI) medication often prescribed to treat acid reflux, ulcers and other issues with the stomach and esophagus. The drug works by preventing the production of acid in the stomach, which helps with conditions that may be exacerbated by excess stomach acid.

Other drugs in the PPI medication class include: Nexium, Nexium IV, Nexium 24 HR, Prevacid, Prevacid IV, Prevacid 24-Hour, Protonix, Zegerid and Zegerid OTC.

Although PPI drugs are widely used, new research reportedly shows that the Prilosec stomach cancer risk may be linked to a bacteria called Helicobacter pylori.

H. pylori infections can cause ulcers in the digestive system and, in some cases, can lead to stomach cancer. Unfortunately, H. pylori can be picked up from food, water, utensils, and saliva – making it hard to avoid. The combination of H. pylori and PPI drug usage may increase the risk of stomach cancer more than the two factors separately.

“While PPIs are one of the most commonly used medications for treating reflux disease as well as dyspepsia, clinicians should exercise caution when prescribing long-term PPIs, even to patients who have H. pylori eradicated,” said lead researcher Dr. Wai Keung Leung, according to WebMD.

Leung’s study examined 63,400 patients who were treated with antibiotics and PPI medications, a combination intended to kill the H. pylori bacteria in the intestines. The treatment was administered to patients over the course of seven days between the years of 2003 and 2012. After treatment, each patient’s progress was followed until the participants developed stomach cancer or died, or until the study ended.

The study showed that taking PPI drugs such as Prilosec increased the risk of developing stomach cancer by two to eight times. In comparison, treatment with H2 blockers (Pepcid, Zantac, Tagamet) did not increase the risk.

The longer the PPI drugs were used, the higher the risk was, the study said. In the first year of treatment, the risk reportedly increased by five times. After two or more years, the risk increased by six and after three or more years, the risk increased by eight.

“The advice to PPI users, particularly those with past H. pylori infection, is to be cautious with the prolonged usage of PPIs,” Leung said. “Doctors should review the indications and needs of long-term PPIs in these patients.”

However, not all doctors are convinced that the Prilosec stomach cancer link warrants abandoning PPI drugs altogether. Dr. Sherif Andrawes, director of endoscopy at Staten Island University Hospital, says that treatment must be tailored on an individual basis, and that the benefits of PPI drugs like Prilosec may outweigh the risks in some situations.

“There are medical situations in which PPI therapy is necessary and the risk of side effects is lesser than the risk of developing bleeding or cancer of another area in the GI [gastro-intestinal] tract,” Andrawes said to WebMD.