Chronic cough is a persistent cough that lasts for 8 weeks or more in adults or 4 weeks or more in children. Unlike a temporary cough that may occur due to a cold or flu, a chronic cough can indicate an underlying medical condition that requires diagnosis and treatment.
Causes of Chronic Cough:
Chronic cough can result from a variety of conditions, often related to irritation or inflammation of the airways. Some of the most common causes include:
- Post-nasal drip (upper airway cough syndrome):
- This occurs when excess mucus drips down the back of the throat from the sinuses or nose. It can be caused by allergies, sinus infections, or rhinitis.
- Asthma:
- A condition where the airways become inflamed and narrowed, leading to wheezing, shortness of breath, and coughing, especially at night or early in the morning.
- Gastroesophageal reflux disease (GERD):
- GERD occurs when stomach acid or bile irritates the esophagus, leading to a persistent cough, often worse after eating or when lying down.
- Chronic obstructive pulmonary disease (COPD):
- COPD, including emphysema and chronic bronchitis, is often linked to long-term smoking and causes a chronic cough with mucus production and shortness of breath.
- Infections:
- Persistent cough can result from lingering infections such as bronchitis, pneumonia, or tuberculosis. Even after the infection is gone, a cough may persist for several weeks.
- Medications:
- Some medications, especially ACE inhibitors (used to treat high blood pressure), are known to cause a persistent dry cough as a side effect.
- Allergies:
- Allergic reactions to substances like dust, pollen, mold, or pet dander can lead to a chronic cough, often associated with sneezing, runny nose, or itchy eyes.
- Smoking:
- Smoking damages the lungs and can lead to chronic bronchitis, which is marked by a persistent cough, often with phlegm.
- Interstitial lung disease:
- This is a group of diseases that cause inflammation and scarring of the lung tissue, leading to symptoms such as a persistent dry cough and difficulty breathing.
- Lung cancer:
- Although less common, lung cancer can present with a chronic cough, especially if there is a tumor affecting the airways.
- Other conditions:
- Other less common causes of chronic cough include cystic fibrosis, whooping cough, sarcoidosis, and vocal cord dysfunction.
Symptoms Associated with Chronic Cough:
A chronic cough may be accompanied by a variety of symptoms, depending on the underlying cause:
- Sputum production: Mucus or phlegm may be coughed up, which can indicate an infection, COPD, or chronic bronchitis.
- Wheezing: A high-pitched whistling sound when exhaling, often associated with asthma or COPD.
- Shortness of breath: Difficulty breathing, especially with exertion, common in asthma, COPD, or lung infections.
- Heartburn: A burning sensation in the chest, which can be a sign of GERD causing the chronic cough.
- Nighttime cough: A cough that worsens at night, which may indicate asthma, GERD, or post-nasal drip.
Diagnosis of Chronic Cough:
To diagnose the cause of chronic cough, a healthcare provider may perform the following:
- Medical history: The doctor will inquire about the duration, frequency, and nature of the cough, along with any associated symptoms (such as chest pain or wheezing).
- Physical exam: A thorough examination of the chest and lungs to listen for abnormal sounds, signs of infection, or other issues.
- Chest X-ray: To rule out lung infections, tumors, or other lung-related problems.
- Spirometry or pulmonary function tests: To assess lung function and check for conditions like asthma or COPD.
- Sputum analysis: Testing mucus or phlegm for signs of infection.
- CT scan: A more detailed imaging test that may be needed if the X-ray doesn’t provide enough information.
- Blood tests: To check for infections, allergies, or other systemic conditions that could be causing the cough.
- Allergy tests: If allergies are suspected to be the cause of the cough.
- Esophageal pH monitoring: If GERD is suspected, this test measures acid levels in the esophagus.
Treatment of Chronic Cough:
The treatment of chronic cough depends on the underlying cause. Options may include:
- Medications:
- Cough suppressants: Over-the-counter medicines like dextromethorphan can help suppress the cough temporarily.
- Expectorants: Medications like guaifenesin can thin mucus, making it easier to expel.
- Antihistamines: If allergies are the cause, antihistamines or nasal steroids may help.
- Inhalers or bronchodilators: For asthma or COPD, inhaled medications can help open up the airways.
- Proton pump inhibitors (PPIs): For GERD-related cough, these drugs reduce stomach acid production.
- Antibiotics: If a bacterial infection is the cause of the cough, antibiotics may be prescribed.
- Steroids: In cases of inflammation, corticosteroids (either inhaled or oral) may be used.
- Lifestyle changes:
- Quit smoking: If smoking is the cause of the cough, quitting is essential.
- Avoid allergens: Identify and avoid triggers, such as dust, pollen, pet dander, or mold.
- Elevate the head while sleeping: For GERD-related cough, elevating the head during sleep can help prevent acid reflux.
- Humidification: Using a humidifier may help soothe the throat and ease coughing, especially if the cough is caused by dry air.
- Treating the underlying condition:
- If the chronic cough is related to a specific condition, such as asthma, COPD, or GERD, addressing that condition through appropriate treatment can alleviate the cough.
- Cough therapy:
- Speech therapy or breathing exercises can help retrain the voice box and reduce chronic coughing in some cases.
When to See a Doctor:
It’s important to see a healthcare provider if:
- The cough lasts more than 8 weeks in adults or 4 weeks in children.
- There is coughing up of blood or bloody sputum.
- The cough is associated with shortness of breath, chest pain, or weight loss.
- There is a history of smoking or exposure to other harmful substances.
Complications of Chronic Cough:
- Sleep disturbances: A chronic cough can interfere with sleep, leading to fatigue and difficulty concentrating.
- Chest discomfort: Continuous coughing can cause soreness or pain in the chest.
- Social embarrassment: Persistent coughing may cause people to feel self-conscious or avoid social situations.
- Underlying disease progression: If the chronic cough is due to an untreated condition like asthma or COPD, the underlying disease may worsen over time.
Chronic cough is often a symptom of a treatable condition, but identifying the root cause is crucial for effective treatment and relief.
