A study recently published by the Journal of the American Medical Association (JAMA) has linked proton-pump inhibitors (PPIs), known to consumers as acid reflux medication and includes popular name-brand drugs such as Prilosec (omeprazole), Nexium (esomeprazole), and Prevacid (lansoprazole), to causing serious vitamin B12 deficiencies in several users. Vitamin B12 deficiencies were also found in several individuals taking H2 receptor antagonists (H2RAs), which include Tagamet (cimetidine), Pepcid (famotidine), and Zantac (ranitidine).

According to Reuters Dr. Douglas Corley, a gastroenterologist at the Kaiser Permanente Division of Research in Oakland, California, along with a team of researchers studied medical records of approximately 26,000 residents of Northern California that had been diagnosed with a B12 deficiency between 1997 and 2011 and compared them to roughly 185,000 who had healthy vitamin B12 levels.

Corley’s observations discovered that 12 percent of the individuals in the group that were diagnosed with a vitamin B12 deficiency had been taking PPIs for at least two years. It was also discovered that 4 percent with the vitamin deficiency had been taking H2RAs for several years as well. Higher dosages of the medications were also associated with vitamin B12 deficiencies in users. The study ultimately concluded that individuals who took PPIs for more than two years were 65 percent more likely to have a vitamin B12 deficiency.

The researchers explain that because PPIs and H2RAs limit the production of acid in the stomach. According to the JAMA study, medications could “theoretically increase the population’s risk of vitamin B12 deficiency” as stomach acid helps with the absorption of vitamin B12.

“Studies conducted on drugs already on the market sometimes reveal risks that pharmaceutical companies fail to warn about,” commented Megan McBride, a lawyer with the Levin, Papantonio law firm who represents individuals who have developed acute liver failure from acetaminophen, the main ingredient found in the over-the-counter pain reliever, Tylenol.

Additional studies are needed to validate the link between PPIs and H2RAs to the development of a vitamin B12 deficiency. However, individuals who use acid reflux medications are encouraged to continue to monitor their health while on these medications.

Krysta is a writer and researcher with Ring of Fire. Follow her on Twitter @KrystaLoera.