Children born to mothers who take popular heartburn medications like proton pump inhibitors (PPIs) and H2 blockers may have a greater risk of developing childhood asthma, according to new research.
The study, published this month in the Journal of Allergy and Clinical Immunology, reviewed data from eight studies involving more than 1.6 million patients who received follow-ups anywhere between five to 14 years. After analyzing the data, researchers found that children whose mothers had been prescribed heartburn medications were at least a third more likely to have visited a doctor for asthma.
The researchers, led by the universities of Edinburgh and Tampere in Finland, looked at the two main types of heartburn medications. They found that PPIs — like Prevacid (lansoprazole), Prilosec (omeprazole) and Nexium (esomeprazole) — were associated with a 30 percent increased risk of childhood asthma. H2 blockers — such as Pepcid (famotidine), Zantac (ranitidine) and Tagamet (cimetidine) — had an even higher association of risk at 46 percent.
“Our study reports an association between the onset of asthma in children and their mothers’ use of acid-suppressing medication during pregnancy,” said Aziz Sheikh of the University of Edinburgh. “It is important to stress that this association does not prove that the medicines caused asthma in these children and further research is needed to better understand this link.”
Heartburn is a common affliction among pregnant women due to changes in hormones and internal pressures. Acid reflux happens when stomach acid is forced back up into the esophagus. Symptoms include stomach pain, difficulty swallowing, regurgitation of food and more.
PPIs and H2 blockers work in similar ways to treat heartburn. Both suppress gastric acid secretion to prevent it from going up into the esophagus.
Scientists are not sure why heartburn medications are linked with asthma, but some have thought they may affect the immune system. Studies of the link have been inconclusive, however. Another working theory is that the drugs allow undigested food allergens to pass through to the baby, according to the New York Times.
Even though the study found higher instances of asthma symptoms reported from children of mothers taking heartburn medication, the authors say that it may not be the cause.
“We don’t yet know if the heartburn medication itself is contributing to the development of asthma in children, or if there is common factor we haven’t discovered yet that causes both heartburn in pregnant women and asthma in their children,” Dr. Samantha Walker, Director of Policy and Research at Asthma UK, said. “The study points us towards something that needs further investigation which is why we need to see more research carried out into the causes of asthma, a condition that affects 5.4 million people in the UK alone.”
Further research needs to be done, but lead researcher Sheikh told the New York Times that heartburn can be treated in other ways, including chewable antacid tablets.
“Gastric reflux is common in pregnancy and in the majority of women, it can be managed with lifestyle or diet changes,” he said.
PPIs Have History of Serious Side Effects
PPIs are among the highest-selling drugs in the United States. In 2014, Nexium alone brought in nearly $6 billion. The prevalence of PPIs has also been accompanied by alarming studies, complaints from patients and warnings from the U.S. Food and Drug Administration.
The asthma review is just the latest to link the popular heartburn medications with potentially serious side effects.
In November, researchers presented findings that PPIs may increase people’s overall risk of stroke by 21 percent. When taken at its highest doses, Protonix (pantoprazole) increased the risk by 94 percent. The people at most risk were those who were exposed to higher doses for longer periods of time.
More recently, a study published in the Journal of Clinical Pharmacology found that both PPIs and H2 blockers increased a patient’s risk of developing two gut infections. Those who took heartburn medications were 3.7 times more likely to develop a potentially deadly infection called C. difficile.
The discovery of previously unknown side effects has resulted in countless lawsuits from patients claiming that makers of heartburn medications failed to warn users of risks.