Popular Acid Reflux Medications Linked to Higher Risk of Migraine

People who take common prescription medications for reducing stomach acid may be more likely to have migraines and other severe headaches compared with people who don’t take them, according to a new study from the University of Maryland.

The study also found that in a small subset of patients who took a specific kind of acid reflux medication known as H2 blockers, those who consumed the daily recommended amount of magnesium were more likely to have migraines than those who consumed less.

“Given the wide usage of acid-reducing drugs and these potential implications with migraine, these results warrant further investigation,” said Margaret Slavin, the study’s lead author and an associate professor of nutrition and food science at UMD. “These drugs are often considered to be overprescribed, and new research has shown other risks tied to long-term use of proton pump inhibitors (another type of medication used for acid reflux), such as an increased risk of dementia.”

The study was published online Wednesday in Neurology Clinical Practice, an official journal of the American Academy of Neurology.

Acid reflux occurs when stomach acid flows into the esophagus, usually after a meal or when lying down. People with acid reflux can experience heartburn and ulcers, and may develop gastroesophageal reflux disease (GERD), which can lead to cancer of the esophagus.

Although the study did not establish a mechanism demonstrating that acid-reducing drugs or supplements cause migraines, the researchers advised users who have migraines or severe headaches to discuss the possible connection with their doctor to determine if they should stop the medications.

Slavin and her colleagues looked at data on 11,818 people who provided information on use of acid-reducing drugs and whether they had migraines or severe headaches in the past three months. The study did not consider over-the-counter medications like Prilosec or Pepcid that contain the same drugs at non-prescription strength.

For participants taking proton pump inhibitors, such as omeprazole and esomeprazole, 25% had migraines or severe headaches, compared to 19% of those who were not taking the drugs. Another 25% of those taking H2 blockers, such as cimetidine and famotidine, had severe headaches, compared to 20% of those who were not taking those drugs. And 22% of those taking antacid supplements like Tums had severe headaches, compared to 20% of those not taking antacids.

Adjusting for other factors that could affect the risk of migraines, such as age, sex and use of caffeine and alcohol, researchers found that people taking proton pump inhibitors were 70% more likely to have migraines than people not taking acid-reducing drugs. Those taking H2 blockers were 40% more likely and those taking antacid supplements were 30% more likely.

Other studies have shown that people with gastrointestinal conditions may be more likely to have migraines, and it would be easy to assume that people taking drugs for acid reflux are more susceptible to migraines simply because of their GI condition, the researchers said. But a previous study from Britain showed an increase in migraine rates after people started taking proton pump inhibitors, and U.S. Food and Drug Administration data reveals a higher reported rate of migraines as an adverse event associated with acid reflux medications.

“We don't yet know what’s causing what,” Slavin said, “but the relationship between gastrointestinal conditions and migraines is not likely to fully explain the tie between acid-reducing drugs and migraine found in the study.”

Slavin noted that the total number of people in the study who reported taking acid-reducing drugs was small, just 2,340, and only 75 were taking HR blockers. Future studies with more participants will be needed to help untangle the remaining questions.

This article was adapted from a press release produced by the American Academy of Neurology.