Medically reviewed by Steve Kim, MD on March 7, 2016 — Written by Michael Kerr

Acid Reflux and Asthma

People with asthma are twice as likely as those without asthma to develop the chronic form of acid reflux known as gastroesophageal reflux disease (GERD) at one time or another. In fact, research has shown that more than 75 percent of adults with asthma also have GERD. The exact connection between GERD and asthma isn’t entirely clear. However, researchers have a few theories as to why the two conditions may coincide.

Why GERD May Trigger Asthma

One possibility is that the repeated flow of stomach acid into the esophagus damages the lining of the throat and the airways to the lungs. This can lead to breathing difficulties as well as a persistent cough. The frequent exposure to acid may also make the lungs more sensitive to irritants, such as dust and pollen, which are all known to trigger asthma.

Another possibility is that acid reflux may trigger a protective nerve reflex. This nerve reflex causes the airways to tighten in order to prevent the stomach acid from entering the lungs. The narrowing of the airways can result in asthmatic symptoms, such as shortness of breath.

Why Asthma May Trigger GERD

Just as GERD can make asthma symptoms worse, asthma can exacerbate and trigger symptoms of acid reflux. Pressure changes that occur inside the chest and abdomen during an asthma attack, for example, are believed to aggravate GERD. As the lungs swell, the increased pressure on the stomach may cause the muscles that usually prevent acid reflux to become lax. This allows stomach acid to flow back up into the esophagus.

Symptoms

Heartburn is the main GERD symptom that adults face. In some people, however, GERD can occur without causing heartburn. Instead, symptoms may be more asthmatic in nature, such as a chronic dry cough or difficulty swallowing.

Your asthma may be connected to GERD if:

  • asthma symptoms begin in adulthood
  • asthma symptoms get worse following a large meal or exercise
  • asthma symptoms occur while drinking alcoholic beverages
  • asthma symptoms happen at night or while lying down
  • asthma medications are less effective than usual
  • It can be difficult to identify symptoms of GERD in children, especially if they’re very young. Infants under age 1 will often experience symptoms of acid reflux, such as frequent spitting up or vomiting, with no harmful effects.

In general, infants and young children with GERD will:

  • become irritable
  • arch their backs often (usually during or immediately following feedings)
  • refuse to eat
  • experience poor growth (both in terms of height and weight)

In older toddlers and children, GERD may cause:

  • nausea
  • heartburn
  • repeated regurgitation
  • symptoms of asthma, such as coughing, shortness of breath, and wheezing