Overview Illustration - COPD

COPD Overview

Chronic obstructive pulmonary disease (COPD) is a group of chronic, progressive lung diseases that limit airflow to the lungs and cause difficulty breathing. The disease generally develops after long-term exposure to irritants like cigarette smoke, dust, chemical fumes, and air pollution. 

The hallmark symptoms of COPD are shortness of breath, chronic cough, and wheezing.  Doctors use tests and procedures, including blood work, imaging scans, and lung function tests, to diagnose COPD. 

There is no cure for COPD, but it is treatable. Treatments for COPD help manage symptoms, improve breathing, and slow disease progression. A combination of lifestyle changes, medications, supplemental oxygen, and rehabilitation therapies are the most common treatments for the condition. Worldwide, over 10% of adults over 40 live with COPD.

Types of COPD

There are two main types of COPD associated with damage to the airways and breathing difficulties. These are called chronic bronchitis and emphysema.

Chronic Bronchitis 

Chronic bronchitis occurs when the air passages (bronchial tubes) become inflamed and narrowed, restricting airflow through them. As a result, mucus builds up in the airways, which results in chronic cough and mucus (phlegm) production. The combination of narrowed airways and excess mucus makes breathing difficult.


Emphysema occurs when air sacs in the lungs are damaged. The air sacs are ordinarily elastic, but damage from exposure to irritants causes them to become saggy and impairs the air sacs’ ability to move oxygen and carbon dioxide in and out of the lungs. 

Most people with COPD have both chronic bronchitis and emphysema.

COPD Symptoms

Symptoms of COPD develop slowly, and many people do not know they have the condition when it first develops. When symptoms do appear, they usually begin in mid-life, and many people dismiss them as a sign of aging. 

Common Symptoms

COPD symptoms range in severity and vary from person to person. The most common symptoms of COPD include:

  • Shortness of breath that worsens with physical activity 
  • Chronic cough with or without mucus 
  • Intermittent wheezing
  • Frequent respiratory infections
  • Fatigue 
  • Trouble taking a deep breath 
  • Chest tightness 

Exacerbation Symptoms

It’s not uncommon for a person with COPD to experience a sudden increase in the number and severity of symptoms. This is called an exacerbation or flare-up and is associated with worsened lung function, reduced quality of life, and the need for hospitalization or emergency medical care in some cases.

Sometimes an exacerbation is a sign that a person’s COPD is progressing. As COPD advances, people may experience more severe and new symptoms:

  • More frequent breathlessness, even with day-to-day activities such as getting dressed 
  • Worsened cough
  • Increased mucus production 
  • Change in the color of mucus (phlegm) from transparent to colored (yellow, green, or brown) 
  • Intense fatigue 
  • Trouble sleeping
  • Morning headaches 

End-Stage Symptoms

As COPD progresses, people with the condition tend to experience more severe and frequent symptoms. End-stage COPD symptoms can include:

  • Difficulty breathing, even when resting
  • Loss of appetite 
  • Swelling in the legs, feet, and ankles 
  • Rapid heart rate 
  • Recurrent respiratory infections
  • Rapid weight loss 
  • Severe fatigue 
  • Morning headaches
  • Worsened cough 
  • Confusion

What Causes COPD? 

COPD occurs when the airways and air sacs become irritated and damaged. This causes them to become narrowed, inflamed, and less stretchy, limiting airflow in and out of the lungs. Excess mucus production can also block or clog the airways, reducing airflow.

Long-term exposure to cigarette smoke or harmful irritants, such as dust, fumes, chemicals, and air pollution, can damage the lungs and airways. Over time, this damage causes the airways and air sacs to become damaged and less stretchy, which leads to difficulty breathing. 

Risk Factors

Certain risk factors can increase a person’s risk of developing COPD:

  • Smoking or exposure to second-hand smoke 
  • Occupational exposure to chemicals, dust, vapors, or fumes 
  • Indoor and outdoor air pollutants such as smog, mold, dust mites, asbestos, and combustible pollutants (e.g., firewood smoke, furnaces that use gas or coal) 
  • Frequent or severe respiratory infections in childhood that stunt lung growth 
  • Asthma in childhood 
  • Alpha-1 antitrypsin deficiency, a rare genetic condition 

How Is COPD Diagnosed? 

If you have symptoms of COPD, your healthcare provider will investigate to determine the cause. They may ask for a detailed personal and family medical history and perform a physical examination. During the exam, they will use a stethoscope to listen to your lungs as you breathe to check for crackling or wheezing sounds.

In addition to the physical exam, your provider may order additional procedures and tests to diagnose COPD, including:

  • Spirometry: A non-invasive lung function test that measures the maximum amount of air you can hold in your lungs and how quickly you can blow the air out.  
  • Six-minute walk test: You will walk for 6 minutes at your usual pace while doctors measure your blood pressure, pulse, and oxygen levels to check on how well your lungs function. 
  • Complete blood count (CBC): A blood test that helps your doctor determine if you have an infection or low iron (anemia). 
  • Arterial blood gas (ABG): A blood test that measures how much oxygen and carbon dioxide are in your blood to determine how well your lungs are functioning. 
  • Alpha-1 antitrypsin (AAT) deficiency: A genetic test that checks for levels of AAT in the blood. Low levels of AAT may be a sign of a rare genetic condition called AAT deficiency, which is linked to an increased risk of COPD. 
  • Computed tomography (CT) scan: An imaging test that takes detailed pictures of your lungs and other structures in your chest so doctors can look for damage and scarring in the airways. 
  • Chest X-ray: An imaging test that takes pictures of the structures in and around your chest to check for signs of lung tissue damage and scarring. 

Stages of COPD

When you are diagnosed with COPD, your doctor will determine the stage (grade) of the disease using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) staging criteria. COPD staging is based on several factors:

  • Spirometry (breathing test) test results 
  • Your symptoms and how they impact your life 
  • Your risk of exacerbations 

Stages of COPD include:

  • Stage 1: Mild COPD
  • Stage 2: Moderate COPD
  • Stage 3: Severe COPD
  • Stage 4: Very severe COPD 

COPD is also grouped based on a person’s symptoms and risk of exacerbation:

  • Group A: Few symptoms, few of exacerbations 
  • Group B: More symptoms, few of exacerbations 
  • Group E: Frequent or severe exacerbations, regardless of symptoms

Treatments for COPD

The goals of treating COPD include improving airflow to make breathing easier, preventing disease progression, reducing exacerbations and complications, and improving quality of life.

Treatments vary depending on the severity of the condition but generally include a combination of lifestyle interventions, prescription medications, oxygen therapy, and pulmonary rehabilitation. Surgery may be an option for some people with severe COPD.

Lifestyle Interventions

Making healthy lifestyle choices is an essential part of treating COPD. Lifestyle interventions for COPD include:

  • Quitting smoking
  • Limiting exposure to lung irritants: secondhand smoke, pollutants, gasses, and fumes 
  • Regular exercise 
  • Eating a healthy, balanced diet 
  • Getting vaccinated for influenza, pneumococcal viruses, and COVID-19
  • Avoiding contact with people who have respiratory infections 

Prescription Medications 

Medications to reduce inflammation and swelling to open the airways, decrease mucus production, and improve lung function are often prescribed to treat COPD. Many drugs are breathed in through inhalers or nebulizer devices, and some are taken orally as pills. Prescription medicines for COPD include:

  • Bronchodilators: These relax the muscles around the airways to make breathing easier. Some take a while to work but last about 12 to 24 hours, and others are fast-acting to help relieve sudden shortness of breath. 
  • Corticosteroids: These reduce inflammation and swelling to open the airways. Corticosteroids are usually inhaled, but pills may be prescribed during a flare-up.
  • Antibiotics: These medications treat bacterial respiratory infections to help clear the infection and prevent complications.
  • Oxygen therapy: Supplemental oxygen may be recommended if you have low blood oxygen levels when at rest, during physical activities, or while sleeping.

Pulmonary Rehabilitation 

Pulmonary rehabilitation is a supervised program that includes physical exercise, education, and support. These programs can help you improve your endurance and breathing ability during exercise and daily activities. Pulmonary rehab programs are generally offered in group settings, so you can meet others with COPD to give and receive support.


Surgery may be an option for some people with severe and frequent symptoms that are not well-managed with medications. Surgical procedures improve lung capacity and make it easier to breathe. Lung surgeries for COPD include:

  • Bullectomy
  • Lung volume reduction surgery 
  • Lung transplant

How to Prevent COPD 

Smoking is the most common cause of COPD. If you smoke, the best way to prevent COPD is to quit. Talk to your healthcare provider about products and programs that can help you kick the habit. 

If you don’t smoke, you can lower your risk of COPD by avoiding or limiting your exposure to lung irritants, such as secondhand smoke, dust, chemical fumes, and environmental pollutants.

Comorbid Conditions

COPD affects more than just the lungs—the heart, blood vessels, muscles, brain, and other organs can also be affected. Research shows that people with COPD have a higher risk of developing other health conditions, including:

Living With COPD 

COPD is a life-altering condition that affects nearly every part of your life—work, relationships, and even your ability to perform daily tasks. Fortunately, many people with COPD can live well with the condition by making healthy lifestyle choices and following their treatment regimen.

More than 16 million Americans live with COPD, and you may find it valuable to join a COPD support group to connect with others with similar experiences. In addition to following your treatment plan, talk to your healthcare provider about support resources and effective coping strategies to help you enjoy a good quality of life with COPD.

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Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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