Yes, gastroesophageal reflux disease (GERD) is a commonly identified cause of chronic cough, defined as a cough lasting eight weeks or longer. GERD occurs when the lower esophageal sphincter, a ring of muscle separating the esophagus from the stomach, weakens or relaxes inappropriately. This allows stomach contents to flow back up, or reflux, which irritates the lining of the esophagus and throat. This backwash can lead to various symptoms, including a persistent cough. Estimates suggest that GERD may be associated with 25% or more of all chronic cough cases, often presenting even without the classic symptom of heartburn.
How Acid Reflux Triggers a Cough
The mechanism by which acid reflux stimulates a cough involves two primary physiological pathways, known as the reflex theory and the microaspiration theory. The reflex theory proposes that the presence of stomach acid in the lower part of the esophagus irritates sensory nerve endings. These nerves, which are part of the vagus nerve network, then trigger a protective reflex arc to the brain’s cough center. This esophago-tracheobronchial reflex causes a cough even though the stomach contents have not physically reached the airways. Because the respiratory and digestive tracts share an embryonic origin, stimulation in the esophagus can provoke a reaction in the broncho-pulmonary system.
This process can be activated by both acidic and non-acidic reflux episodes, leading to a heightened sensitivity of the cough reflex. The microaspiration theory involves the direct irritation of the upper airways. In this scenario, tiny droplets of acidic or non-acidic stomach contents travel up the esophagus and are inhaled into the larynx or trachea. This direct contact with the delicate airway lining causes inflammation, which then initiates a chronic, protective cough.
Digestive enzymes like pepsin, found in the refluxate, can also cause damage to the respiratory mucosa when aspirated, even at a pH level that is not highly acidic. Dysfunction of the upper esophageal sphincter or impaired protective reflexes in the throat can increase the risk of this microaspiration. In some patients, a cycle can develop where the physical action of coughing itself creates pressure that worsens the reflux, further intensifying the cough.
Identifying a Reflux-Related Cough
A cough caused by GERD often presents with characteristics that distinguish it from a cough related to other respiratory illnesses. Typically, a reflux-related cough is dry and non-productive, meaning it does not produce mucus or phlegm. The timing of the cough is a strong indicator, as it frequently worsens when a person lies down, especially at night. This occurs because the horizontal position makes it easier for stomach acid to flow up the esophagus. Similarly, coughing may increase shortly after consuming a large meal, when the stomach is full and acid production is high.
Associated symptoms can further suggest GERD as the underlying cause, even if classic heartburn is absent. These symptoms include a sensation of a lump in the throat, frequent throat clearing, or hoarseness due to irritation of the vocal cords. Other clues may include a sour taste in the mouth, tightness in the throat, or a cough that does not improve after standard cold or allergy treatments.
Treatment Options for GERD-Induced Cough
Treating a GERD-induced cough focuses on reducing the frequency and severity of acid reflux through a combination of lifestyle changes and medical interventions. Lifestyle modifications are generally the first line of defense and can significantly alleviate symptoms. Eating smaller, more frequent meals, instead of large ones, can reduce pressure on the lower esophageal sphincter.
Avoiding common dietary triggers is also an important step, with foods like caffeine, alcohol, fatty or fried foods, chocolate, and acidic items such as citrus fruits being the most common culprits. Patients should avoid lying down for at least two to three hours after eating to give the stomach time to empty its contents. Elevating the head of the bed by six to eight inches, using a wedge block rather than extra pillows, utilizes gravity to keep stomach acid down, which is particularly helpful for nighttime coughing. Maintaining a healthy body weight and quitting smoking are also advised, as excess weight and nicotine both weaken the lower esophageal sphincter.
If lifestyle adjustments do not provide sufficient relief, medical treatments are often introduced to reduce stomach acid production. Over-the-counter and prescription options include antacids for quick, temporary neutralization of stomach acid. H2 receptor blockers decrease acid production by blocking histamine receptors in the stomach lining. Proton pump inhibitors (PPIs) are generally the most effective class of medication, as they powerfully suppress acid secretion and allow the esophagus to heal. Consult a healthcare provider for an accurate diagnosis and treatment plan, since a chronic cough can also be a sign of other serious health issues.