Most chronic coughs are caused by common conditions like postnasal drip, asthma, or acid reflux. However, in rare cases, chronic cough may be a symptom of less common or often overlooked conditions. These rare causes should be considered, especially when standard treatments don’t resolve the issue.
1. Idiopathic Pulmonary Fibrosis (IPF)
- IPF is a progressive lung disease where lung tissue becomes scarred and stiff.
- This scarring reduces lung function and often leads to a dry, persistent cough.
- Symptoms may include shortness of breath, fatigue, and crackling sounds when breathing.
2. Eosinophilic Bronchitis
- This condition involves inflammation of the airways caused by eosinophils, a type of white blood cell.
- Unlike asthma, it does not cause wheezing or airflow obstruction, making it easy to miss.
- It often presents as a dry, non-productive cough lasting for weeks or months.
3. Sarcoidosis
- A rare inflammatory disease that causes small clumps of inflammatory cells (granulomas) to form, most commonly in the lungs.
- Chronic dry cough, chest pain, and shortness of breath are common symptoms.
- The exact cause is unknown, but it may be linked to an abnormal immune response.
4. Laryngopharyngeal Reflux (LPR)
- Sometimes called “silent reflux,” LPR is similar to acid reflux but affects the throat and voice box.
- It can cause a chronic cough, hoarseness, throat clearing, and a sensation of a lump in the throat.
- It often occurs without classic heartburn symptoms, making diagnosis challenging.
5. Bronchiolitis Obliterans (Popcorn Lung)
- This is a rare but serious lung disease that blocks the smallest airways (bronchioles) due to inflammation and scarring.
- It may develop after viral infections, lung transplants, or exposure to toxic chemicals like diacetyl.
- Symptoms include dry cough, wheezing, and difficulty breathing.
6. Tracheomalacia
- A structural abnormality where the windpipe (trachea) is weak or collapses, especially during breathing or coughing.
- It can be congenital or acquired due to trauma, infection, or long-term intubation.
- It causes noisy breathing (stridor), frequent infections, and a barking cough.
7. Pulmonary Arteriovenous Malformations (PAVMs)
- These are abnormal connections between arteries and veins in the lungs.
- While many people have no symptoms, some experience coughing, shortness of breath, or coughing up blood (hemoptysis).
- They are often linked to a genetic disorder called hereditary hemorrhagic telangiectasia (HHT).
8. Drug-Induced Cough (e.g., ACE Inhibitors)
- Some blood pressure medications, especially ACE inhibitors like lisinopril or enalapril, can cause a chronic, dry cough.
- The cough usually begins within weeks of starting the medication and stops once it’s discontinued.
When to Seek Medical Attention
If you’ve had a cough lasting more than 8 weeks with no improvement—or if you’ve tried treatment for common causes without relief—you should consult a healthcare provider. A thorough workup may include:
- Chest X-ray or CT scan
- Pulmonary function tests
- Allergy or reflux evaluations
- Referral to a pulmonologist or ENT specialist
Key Takeaway
Chronic cough isn’t always caused by something simple. While rare, the conditions above can lead to serious complications if not diagnosed early. If you’re experiencing a persistent cough, especially with other symptoms like fatigue, breathlessness, or weight loss, don’t ignore it—early diagnosis can lead to better outcomes.