ConditionLungs & breathing
Lung Disease: Types, Symptoms and Diagnosis
Lung disease is any condition that stops the lungs working properly. Doctors group lung diseases by the part affected: the airways (asthma, COPD, bronchiectasis, cystic fibrosis), the lung tissue (pulmonary fibrosis, sarcoidosis, pneumonia), the blood vessels (pulmonary embolism, pulmonary hypertension) and the pleura and chest wall. Common symptoms are breathlessness, a lasting cough, wheezing, chest tightness and coughing up mucus or blood. Smoking is the leading preventable cause.
Also called: Pulmonary disease, respiratory disease, lung disorders, chronic lung disease
At a glance
- What it is
- Any disease affecting the airways, lung tissue, lung blood vessels or the lining around the lungs.
- Most common
- Asthma, COPD, pneumonia, lung cancer, interstitial lung disease, sleep apnea.
- Main symptoms
- Breathlessness, cough lasting over 3 weeks, wheeze, chest tightness, mucus, coughing blood.
- Main causes
- Smoking, infections, air pollution, workplace dusts and chemicals, genetics, autoimmune disease.
- Key tests
- Spirometry, chest X-ray, CT scan, oxygen levels and blood tests.
When to get help
Call 911 or go to the ER
- Severe breathlessness, being unable to speak in full sentences, or blue or gray lips
- Sudden sharp chest pain with breathlessness, or coughing up more than a few spoonfuls of blood
- Confusion or extreme drowsiness with breathing difficulty
See a doctor within a day or two
- Breathlessness that is getting worse over hours to days
- Fever with cough, chest pain and fast breathing
- A flare of asthma or COPD not responding to your usual treatment
- Swelling of one leg with breathlessness
Book a routine appointment
- A cough lasting more than 3 weeks, or a change in a long-standing cough
- Breathlessness with everyday activities that is new or worsening
- Coughing blood even once, especially if you smoke or used to
- Unexplained weight loss with cough or breathlessness
Types of lung disease
Airway diseases
These narrow or block the tubes that carry air.
| Disease | Key features |
|---|---|
| Asthma | Variable wheeze, cough and tightness, often triggered by allergens, exercise or infections. Reversible |
| COPD | Emphysema and chronic bronchitis, mostly from smoking. Persistent airflow limitation |
| Bronchiectasis | Permanently widened airways with daily mucus and repeated infections |
| Cystic fibrosis | Inherited thick mucus, infections from childhood |
| Bronchiolitis | Small airway inflammation, common in infants with RSV |
Lung tissue (interstitial and parenchymal) diseases
These affect the air sacs and the tissue between them.
- Interstitial lung disease including idiopathic pulmonary fibrosis: scarring that stiffens the lungs
- sarcoidosis: inflammatory clusters (granulomas)
- pneumoconioses: from dusts like coal, silica and asbestos
- hypersensitivity pneumonitis: from inhaled organic dusts such as bird proteins and molds
- pneumonia: infection of the air sacs
Blood vessel diseases
- pulmonary embolism: a blood clot in the lung arteries
- pulmonary hypertension: high pressure in the lung arteries, straining the right side of the heart
Pleural and chest wall diseases
- pleural effusion: fluid around the lung
- pneumothorax: air around the lung causing collapse
- mesothelioma: cancer of the pleura, linked to asbestos
- chest wall deformities and neuromuscular weakness
Lung cancer
Lung cancer is the leading cause of cancer death in the US. Most cases are linked to smoking, but it also occurs in people who never smoked.
Infections
Pneumonia, tuberculosis, COVID-19, influenza, RSV and fungal infections.
Sleep-related breathing disorders
Obstructive sleep apnea affects breathing at night and causes snoring and daytime sleepiness.
Common symptoms
- shortness of breath, especially with exertion
- cough lasting more than 3 weeks
- wheezing
- chest tightness or pain
- mucus (sputum) production, especially daily
- coughing up blood (hemoptysis)
- fatigue and reduced exercise ability
- frequent chest infections
- finger clubbing in some lung diseases
- swollen ankles from heart strain in advanced disease
Causes and risk factors
- smoking and vaping: the leading cause of COPD and lung cancer
- secondhand smoke
- air pollution and wildfire smoke
- occupational exposures: silica, coal, asbestos, chemicals, mold and organic dust
- radon gas in homes
- infections, especially in childhood
- genetics: cystic fibrosis, alpha-1 antitrypsin deficiency
- autoimmune diseases: rheumatoid arthritis, scleroderma
- medicines and radiation therapy
- premature birth
How lung disease is diagnosed
- history and examination: symptoms, smoking, work and home exposures, family history
- pulse oximetry: oxygen saturation
- spirometry: measures how much and how fast you can blow out. Shows obstructive (asthma, COPD) or restrictive patterns
- full lung function tests: lung volumes and gas transfer (DLCO)
- chest X-ray
- CT scan: detailed images of lung tissue. Low-dose CT is used for lung cancer screening
- blood tests: blood count, autoimmune markers, alpha-1 antitrypsin level
- sputum tests for infection
- bronchoscopy: a camera into the airways for biopsies
- sleep studies for sleep apnea
- echocardiogram for pulmonary hypertension
Lung cancer screening
The USPSTF recommends yearly low-dose CT screening for adults aged 50 to 80 with a 20 pack-year smoking history who currently smoke or quit within the past 15 years.
Treatment
Depends on the disease:
- inhalers: bronchodilators and steroid inhalers for asthma and COPD
- antibiotics, antivirals and antifungals for infections
- antifibrotic medicines (nintedanib, pirfenidone) for pulmonary fibrosis
- blood thinners for pulmonary embolism
- oxygen therapy for low blood oxygen
- pulmonary rehabilitation: exercise and education that improves breathlessness and quality of life
- cancer treatments: surgery, radiotherapy, chemotherapy, targeted and immunotherapy
- CPAP for sleep apnea
- lung transplant for selected end-stage disease
Protecting your lungs
- do not smoke or vape, and avoid secondhand smoke
- test your home for radon
- use protective equipment at work
- stay up to date with flu, COVID-19, pneumococcal, RSV (for older adults) and pertussis vaccines
- stay physically active
- check air quality and limit outdoor exertion on poor air days
Frequently asked questions
What are the most common lung diseases?
The most common are asthma, COPD (chronic obstructive pulmonary disease), pneumonia and other respiratory infections, lung cancer, sleep apnea and interstitial lung diseases such as pulmonary fibrosis.
What are the early signs of lung disease?
Early signs include breathlessness with activities that used to be easy, a cough lasting more than 3 weeks, wheezing, daily mucus, chest tightness and frequent chest infections. Coughing blood should always be checked.
What causes chronic lung disease?
Smoking is the leading cause. Others include air pollution, workplace dusts and chemicals, repeated infections, genetic conditions such as cystic fibrosis and alpha-1 antitrypsin deficiency, autoimmune diseases and some medicines.
How do doctors test for lung disease?
Common tests are spirometry and other lung function tests, oxygen saturation, chest X-ray and CT scan. Blood tests, sputum tests, bronchoscopy and sleep studies are used depending on the suspected condition.
Can lung damage be reversed?
Some can. Asthma airway narrowing is reversible, infections heal, and stopping smoking slows COPD decline. Scarring in emphysema and pulmonary fibrosis cannot be reversed, but treatment and rehabilitation can slow progression and improve symptoms.
Sources
This guide was written from current patient and clinical guidance, including:
- American Lung Association: Lung disease lookup
- National Heart, Lung, and Blood Institute (NHLBI): Lung diseases
- Global Initiative for Chronic Obstructive Lung Disease (GOLD): 2025 Report
- CDC: Chronic obstructive pulmonary disease
- World Health Organization: Chronic respiratory diseases
- NHS: Lung health