Acid Blockers Linked with B12 Deficiency

People who take drugs to prevent acid reflux may have a higher risk of vitamin B12 deficiency, a new study finds. The study compared data on 2 groups of people. Nearly 26,000 had a vitamin B12 deficiency. The other 185,000 did not. About 12% of those with low vitamin B12 had taken drugs called proton pump inhibitors for more than 2 years. These are the most powerful drugs to prevent acid reflux. They include lansoprazole (Prevacid), esomeprazole (Nexium) and omeprazole (Prilosec). Among those with normal vitamin B12 levels, only 7.2% took these drugs. That means the long-term users of the medicines had a 65% higher risk of vitamin B12 deficiency. Risk was about 25% higher for people who took different anti-reflux drugs, known as H2 blockers. The study only shows a link between these drugs and low vitamin B12. It does not prove that one causes the other.