Millions of people take proton pump inhibitors (PPIs) every day for acid reflux, heartburn, and stomach ulcers. These medications include common brands such as Prilosec, Nexium, Prevacid, and Protonix. While they are generally considered safe for short-term use, new research has raised concerns about taking them for many years without regular medical review.

A major study involving more than 5,700 older adults found that people who had used PPIs for over 4.4 cumulative years had a 33% higher risk of developing dementia compared to those who had never used them. Researchers identified 585 dementia cases during the follow-up period. Short-term use and lower cumulative use were not linked to a significant increase in risk.

However, the picture is not entirely clear. A larger 2025 meta-analysis that reviewed 18 studies and more than 6.3 million participants found no overall statistically significant link between PPIs and dementia. Still, researchers noted higher risks in some groups, particularly adults aged 65 and older, suggesting more research is needed.

Experts stress that the findings should not cause panic or lead people to stop prescribed medications on their own. Instead, they highlight the importance of reviewing long-term PPI use with a healthcare provider. If you or a loved one has been taking acid-reducing medication daily for years, it may be worth discussing whether continued use is still necessary.