Acid Reflux
Acid reflux is a condition in which some of the contents of the stomach are able to migrate up into the esophagus. Normally this is prevented by a small ring of muscle called the lower esophageal sphincter, which normally forms a valve at the intersection of the esophagus and the stomach. This valve can fail, however, for a number of reasons, including indigestion, obesity, and eating right before going to sleep. As a result, some of the stomach contents, including the stomach acid, will "reflux" up the esophagus, where they can cause a burning sensation and damage to the esophageal lining. This reflux can go up as far as the larynx, also known as the "voice box" area.
Asthma
Asthma occurs due to an abnormal activation of the immune system. In this sense, asthma is very similar to other respiratory allergies. In asthmatics, the immune system reacts to a trigger--which can be anything from cold air to dirt and dust--and causes widespread inflammation of the airway tracts. This inflammation causes swelling of the blood vessels, which in turn blocks up the airway, leading to coughing, wheezing and difficulty breathing. It should be noted that these triggers are not the actual cause of asthma, because asthma is caused by a disorder of the immune system. Instead, these triggers only serve to activate the already hypersensitive immune system to cause the inflammation that leads to asthma. As such, the only asthma treatments that actually target the underlying disease are those that act on mediators of the immune system, such as Cromolyn. In many people, the symptoms of asthma may go away over time as the immune system becomes desensitized to these triggers.
Asthma Due to Acid Reflux
According to Fred Little, an expert at the health site MyAsthmaCentral.com, there is a link between acid reflux and asthma. In some cases, especially when acid reflux is able to travel up to the larynx, it is able to also cause a reflex in the bronchial area (the airway), which leads to inflammation and constriction of the airway. This is especially true for asthmatics who already have a sensitive airway immune system. As a result, acid reflux in these people will result in asthmatic symptoms, including wheezing and coughing. This acid reflux may not even be noticeable to an asthmatic (not generating any of the burning sensation that often follows acid reflux), making it appear as if the asthma attack is occurring in the absence of any trigger. It is worth noting that in this case, acid reflux serves as a trigger for an asthmatic reaction, much like dust or smoke does. Acid reflux does not, however, cause the sensitization of the immune system that is the underlying cause of asthma.
