Wednesday, September 29, 2010

How Does Acid Reflux Cause Asthma

Understanding the Connection between Asthma and Acid Reflux


An estimated three-quarters of people diagnosed with asthma also suffer from acid reflux, which has led to considerable research into the relationship between the two conditions. Although some experts have theorized that the coughing associated with asthma causes acid reflux by irritating the chest, many experts believe that acid reflux might actually be responsible for triggering asthma attacks. Others believe the two conditions may interact, with each disorder triggering the other.


Inflammation of the Respiratory Tract


Asthma is a serious disease that causes the respiratory tract to become inflamed and swollen, leading to an increase in mucus generation, coughing, breathlessness and even death. While the exact cause of asthma is not known, genetics appears to play a large role in the development of the condition.


Relaxation of the Lower Esophageal Sphincter


Acid reflux is caused by stomach acids backing up into the esophagus due to relaxation of the lower esophageal sphincter, or LES, which results in heartburn, sore throat, and hoarseness. Some people with no history of acid reflux have been known to develop the condition after beginning treatment with asthma medications.


Leaking Stomach Acids


When acid leaks from the lower esophagus in people with acid reflux, the nerves that run along the neck and into the chest become stimulated. This results in bronchial constriction, wheezing and difficulty breathing. The irritation caused by the leaking acid produces an asthma attack in certain individuals and can worsen a pre-existing asthmatic condition in others.


Pressure Changes in the Chest


Once the lungs have become irritated,and asthma symptoms have developed, the pressure inside the chest increases. This increased pressure forces additional stomach acids to move back up the esophagus, which results in another attack of acid reflux. Once again, the leaking acid may trigger additional respiratory symptoms. Studies have shown that asthma symptoms are increased when acid is injected into the esophagus of asthmatics. This evidence supports the theory that acid reflux causes asthma.


Treatment Side Effects








Evidence also suggests that some asthma medications that are used to dilate the airways during an asthma attack may also increase acid reflux and perpetuate the cycle of symptoms. These medications may significantly relax the lower esophageal sphincter, causing acid to leak from the esophagus and trigger an attack. Therefore, treatment of asthma, whether caused by acid reflux or anther factor, may worsen acid reflux and precipitate an additional asthma attack.

Tags: acid reflux, asthma attack, with asthma, acid reflux, asthma medications