Important: This page is for general information only and is not a diagnosis. If you are worried about a symptom, please see a doctor.

What is a persistent cough?

A cough is called persistent (or chronic) when it lasts more than 3 weeks without an obvious short-term cause such as a cold or the flu. A short cough during a respiratory infection is normal and expected. A cough that keeps going for weeks — or that gets worse over time — always needs a medical assessment to find the cause.

When is a persistent cough a warning sign?

A persistent cough is one of the most common early symptoms of lung cancer. The following features make a cough more likely to need urgent evaluation:

  • The cough has lasted more than 3 weeks and is not improving
  • The cough is getting worse over time, not staying the same
  • You are coughing up blood — even a small amount, even just once. This is called haemoptysis and is always a red flag. See a doctor the same day
  • You have chest pain that is worse when you breathe deeply, cough, or laugh
  • You have shortness of breath during activities that did not cause breathlessness before
  • Your voice has become hoarse without an obvious cause such as a cold or overuse
  • You have unexplained weight loss — losing more than 4–5 kg without trying
  • You feel unusually tired all the time, more than would be expected
  • You have had two or more chest infections (pneumonia or bronchitis) within a year

If you have any of these features alongside a persistent cough, please see a doctor promptly.

Other possible causes

Most chronic coughs are not caused by cancer. Common causes in India include:

  • Post-nasal drip — mucus dripping from the nose into the throat, often from sinusitis or allergies
  • Asthma — causes a dry or wheezy cough, often worse at night or early morning
  • GERD (acid reflux) — stomach acid rising into the throat irritates the airways and triggers coughing
  • Tuberculosis (TB) — a very important cause of chronic cough in India, including in Bihar. TB causes a cough (sometimes with blood), weight loss, night sweats, and fever — symptoms that can overlap with lung cancer. A doctor must distinguish between TB and lung cancer — never treat yourself with TB medications without a proper diagnosis
  • Chronic Obstructive Pulmonary Disease (COPD) — caused by long-term smoking or indoor cooking smoke; produces a daily cough, especially in the morning
  • Respiratory infections — bacterial or viral infections that have not fully resolved

An important point: non-smokers can also get lung cancer. Do not dismiss a persistent cough just because you have never smoked.

Warning signs that need prompt attention

See a doctor the same day if you have:

  • Blood in your sputum (coughed-up material) — even a small streak
  • Severe or sudden shortness of breath
  • Chest pain that is severe or getting worse rapidly

See a doctor within a week if you have:

  • A cough lasting more than 3 weeks with no improvement
  • Any combination of persistent cough, unexplained weight loss, and tiredness
  • A hoarse voice that has lasted more than 3 weeks
  • Recurring chest infections in the same area of the lung

Risk factors for lung cancer in Bihar

Knowing your risk factors does not mean you have cancer, but it helps you understand when to be more alert about symptoms:

  • Bidi and cigarette smoking — the strongest risk factor by far. The longer and more heavily you smoke, the higher the risk. Bidi smoking carries a very high risk because bidi smoke is unfiltered and highly concentrated
  • Secondhand smoke — living with a heavy smoker significantly raises your own risk
  • Indoor cooking smoke — burning wood, dung cakes, or biomass fuel in poorly ventilated kitchens is a known risk factor, especially for women who have never smoked
  • Occupational dust and chemicals — construction work, mining, or working with asbestos or diesel fumes
  • History of tuberculosis (TB) — TB and its scarring can increase the risk of lung cancer years later

What a doctor will do

  1. History and physical examination — the doctor will ask about your cough, smoking history, work, and any other symptoms, and listen to your lungs
  2. Chest X-ray — the first and most important test, available at district hospitals across Bihar. An abnormal area on the X-ray does not confirm cancer but will guide next steps
  3. CT scan of the chest — if the X-ray is abnormal or the symptoms are strongly suggestive, a CT scan gives a more detailed picture. Available at AIIMS Patna, Mahavir Cancer Sansthan, and larger private hospitals in Patna
  4. Sputum test — a sample of coughed-up sputum is sent to a lab. This can diagnose TB, infection, or sometimes cancer cells
  5. Bronchoscopy and biopsy — a thin flexible tube is passed down the airway to look inside the lungs and take a tissue sample if needed. A biopsy is the only way to confirm lung cancer
  6. Further staging tests — if cancer is confirmed, scans are done to see whether it has spread

Where to get help in Bihar

  • Mahavir Cancer Sansthan, Phulwarisharif, Patna — full lung cancer evaluation, CT scan, and oncology services
  • AIIMS Patna — pulmonology and oncology outpatient departments; chest X-ray, CT scan, bronchoscopy
  • Government district hospitals — chest X-ray and sputum TB test as a first step; can refer for further evaluation

See our full hospital directory at /find-care/hospitals/.

For non-emergency advice, call the Indian Cancer Society helpline: 1800-22-1951 (free). For emergencies, call 108 or 112.