Interstitial lung diseases (ILDs) are a group of several disorders that can cause scarring in your lungs. The scar tissue in your lungs affects your lungs’ ability to carry oxygen and can make it harder for you to breathe normally.

In ILDs, scarring damages tissues in or around the lungs’ air sacs, or alveoli, and airways. The lung interstitium is the space between the air sacs and the small blood vessels that surround the air sacs. It contains connective tissue. When you breathe, oxygen from the air passes through your air sacs and lung interstitium and into your blood. At the same time, carbon dioxide moves from your blood through the lung interstitium and into your air sacs.

If you have an ILD, your lung interstitium becomes thick and stiff. This makes it harder for oxygen to move out of the lungs and into the bloodstream and for carbon dioxide to move out of the bloodstream and into the lungs. About 3 out of every 10,000 people in the United States are diagnosed with an ILD every year.

ILDs can be mild, serious, or even life-threatening. Symptoms of ILDs may include shortness of breath, dry cough, chest discomfort, and extreme tiredness.

Your healthcare provider may diagnose your ILD based on your medical and family histories and results from lung tests, blood tests, and genetic testing.

There are many types of ILDs. ILDs may be caused by your genes, lifestyle habits, your environment, medicines, or other medical conditions.

• Some types of ILDs have no known cause, including the most common type, idiopathic pulmonary fibrosis (IPF).
• Childhood ILDs can have the same or different causes as ILDs in adults.
• Exposure to dust or mold in your environment can cause some ILDs, including asbestos-related lung diseases and hypersensitivity pneumonitis.
• Some types are more common in men or women. IPF is more common in men, while lymphangioleiomyomatosis (LAM) primarily affects women.

Treatment for ILDs depends on what type you have and how serious your symptoms are. Your doctor may ask you to avoid substances in your environment that trigger your condition. Treatment for ILDs does not repair the scarring in your lungs. However, early treatment can help slow down or stop lung damage and can help your lungs work better. Your healthcare team can help you learn how to manage your condition to improve your quality of life.

ILDs are caused by damage to your lungs from things in your environment, your lifestyle habits, or another health condition.

When you breathe in, air enters your airways and travels down into your air sacs, or alveoli, in your lungs. Normally, your air sacs are elastic, meaning that their size and shape can change easily. Air sacs can expand when air gets into your lungs and contract to help get air out of your lungs.

When you injure your lungs, your body will normally repair the damage and heal your lungs. If the injury leads to an ILD, the healing process stops working correctly over time. Your body may repair your damaged lungs with scar tissue. Scar tissue can make your air sacs thick and stiff, and your air sacs may not be able to expand and contract properly. This makes it harder for oxygen to move from your lungs into your bloodstream. The scarring also makes it harder for carbon dioxide to move out of your bloodstream and into your lungs to be breathed out. For some ILDs, such as idiopathic pulmonary fibrosis, the cause of this scarring is unknown.

Many things can damage your lungs and raise your risk of an ILD.

• Family history: You have a higher risk of ILDs if a close relative has an ILD. Mutations, or changes in your genes, can make you more likely to develop scar tissue in your lungs.
• Environment and occupation: Exposure to mold, chemicals, or bacteria at work or in your environment can damage your lungs. Breathing in dust from mining and construction work over a long time can raise your risk of asbestos-related lung disease, which is a type of ILD.

Tell your doctor if you think you may have been exposed to asbestos. Your doctor can watch for symptoms or complications and start treatment early, depending on the type of asbestos-related lung disease you have.

• Lifestyle habits: Smoking can damage your lungs or make lung damage worse.
• Medicines: While rare, some antibiotics, heart medicines, and chemotherapy drugs can raise your risk.
• Other health conditions: Conditions such as sarcoidosis, autoimmune diseases, connective tissue disorders, and viral infections such as COVID-19 can damage your lungs. Watch our video on how SARS-CoV-2 affects the lungs to learn more. Additionally, we offer information and resources on how we are working hard to support necessary COVID-19 research.
• Sex: Some ILDs are more common in men or in women. IPF is more common, and causes more serious symptoms, in men. LAM is more common in women. Also, some autoimmune diseases and connective tissue disorders that cause ILDs are more common in women.

Research for your health

The research we support on interstitial lung diseases has led to more and better treatment options to improve the health of people who have lung damage. Through our current research, we hope to better understand how our genes and our immune system affect our risk of developing ILDs.

Symptoms of ILDs may be different depending on the type of ILD you have and how serious it is. They can happen quickly or slowly and get worse over time. Some people may not have symptoms at first, but symptoms can develop as your disease worsens.

Symptoms of ILDs include:

• Shortness of breath
• A dry cough
• Abnormal sounds when you breathe
• Chest pain and discomfort
• Extreme tiredness
• Clubbing, a widening and rounding at the ends of your fingers or toes along with a downward sloping of the nails

Symptoms in children who have ILDs may be different from symptoms in adults. Adults and children can have the same types of ILD, but there are some types that are unique to each group.

Your healthcare provider will diagnose your ILD based on your symptoms, your medical and family histories, your risk factors, and the results from tests and procedures. You may need to see a pulmonologist, a doctor who specializes in lung diseases.

Diagnostic tests

Your healthcare provider may order one of these common tests to help diagnose an ILD.

• Blood tests are used to look for signs of an infection or an autoimmune disease that can cause an ILD.
• Lung tests include imaging tests like chest X-rays and CT scans that take pictures of your lungs. You may also do lung function tests that measure how much air you breathe out or how much air your lungs can hold. These tests help your doctor see how well your lungs are working.

Other tests

Sometimes your doctor may order other tests if they need more information to help diagnose an ILD.

• Bronchoalveolar lavage (BAL): During this test, your healthcare provider will collect fluid from your lungs. This fluid will be tested for high levels of white blood cells and other immune cells or for substances in your environment that can cause lung scarring.
• Lung biopsy: Your healthcare provider will take a very small sample of your lung tissue. Your healthcare provider will check this sample to see if your lung tissue shows signs of inflammation, scarring, or other changes that happen when you have an ILD.

Your treatment for ILDs will depend on the cause of your condition and how serious your symptoms are. Your healthcare provider will work with you to decide on a treatment plan for you.

Treatment for ILDs does not cure your lung damage, but it can prevent lung damage from getting worse and can help you breathe easier.

Healthy lifestyle changes

If your ILD is caused by substances in your environment or at work, you will need to avoid these substances. If you smoke, your doctor will ask you to stop smoking. Smoking can make your lung damage worse and can raise your risk of health problems.

Medicines

Depending on the type of ILD you have, your doctor may prescribe medicine to help you breathe easier. These medicines work in different ways:

• Bronchodilators can relax the muscles around your airways. This helps open your airways and makes breathing easier. Most often, this medicine is taken using a device called an inhaler. Side effects can include dizziness, shakiness, headache, and sleep changes.
• Corticosteroids can help treat inflammation in your lungs. You may take these with an inhaler or as a pill. Common side effects from inhaled corticosteroids include a hoarse voice or a mouth infection called thrush. A spacer or holding chamber on your inhaler can help avoid these side effects. Oral corticosteroids can have more side effects than inhaled corticosteroids, because the medicine goes outside the lungs.
• Antifibrotics (nintedanib and pirfenidone) can help slow down lung damage. These medicines block growth factors in cells that are involved in causing scarring in the lungs. You may need to take these pills each day. Side effects can include nausea, vomiting, tiredness, dizziness, digestive problems, decreased appetite, weight loss, and sensitivity to light.

Oxygen therapy

Oxygen therapy is a treatment that delivers oxygen gas for you to breathe. You can receive oxygen therapy from tubes resting in your nose, a face mask, or a tube placed in your trachea (windpipe). You may need oxygen therapy if you have a condition that causes your blood oxygen levels to be too low.

Oxygen therapy can be given for a short or long period of time in the hospital, another medical setting, or at home. Oxygen poses a fire risk, so you should never smoke or use flammable materials when using oxygen. You may experience side effects from this treatment, such as a dry or bloody nose, tiredness, and morning headaches. Oxygen therapy is generally safe.

Pulmonary rehabilitation

Pulmonary rehabilitation is a supervised program that includes exercise training, health education, and breathing techniques for people who have certain lung conditions, lung problems due to other conditions, or after a lung transplant. Your provider may talk to you about pulmonary rehabilitation to help you breathe easier and improve your quality of life.

Learn more on our Pulmonary Rehabilitation page.

Lung transplant

Lung transplant is surgery to remove a diseased lung and replace it with a healthy lung. Lung transplants are used to improve quality of life and extend the lifespan for people who have severe or advanced chronic lung conditions that do not respond to other treatments.

During a lung transplant, you will have general anesthesia and will not be awake for the surgery. A surgeon will open your chest, cut the main airway and blood vessels, and remove your diseased lung. The surgeon will connect the healthy donor lung, reconnect the blood vessels, and close your chest. After the surgery, you will recover in the hospital for one to three weeks. After leaving the hospital, you will visit your doctor often to make sure that you are recovering well.

To help prevent your body from rejecting the new lung, you will need to take medicines for the rest of your life that suppress your immune system. Practicing good hygiene, getting annual vaccines, and adopting healthy lifestyle choices such as heart-healthy eating and not smoking are very important.

If you have an ILD, it is important to continue your treatment plan. Talk to your healthcare provider about how often you need check-ups and how to monitor your condition.

What kinds of health problems can ILDs cause?

Without treatment, ILDs may cause the following complications:

• Collapsed lung (pneumothorax)
• Frequent lung infections
• High blood pressure in your lungs (pulmonary hypertension) caused by scar tissue in the lungs’ arteries
• In children, problems growing
• Lung cancer
• Respiratory failure
• Right-sided heart failure, which is often a result of pulmonary hypertension
• Venous thromboembolism, including deep vein thrombosis and pulmonary embolism

Following your treatment plan can help prevent these problems. Talk to your doctor if your symptoms change or get worse.

Manage your condition

Your doctor may ask you to take the following steps to help avoid complications:

• Avoid substances in your environment that can make your ILD worse.
• Get routine follow-up care. You may need repeated lung tests to see whether your lung damage is getting worse. Tell your doctor if your symptoms get worse or if you get new symptoms.
• Get routine vaccines. Pneumococcal, flu (influenza), and COVID-19 vaccines can help prevent lung infections that can lead to more lung damage.
• Make healthy lifestyle changes. If you smoke, find support to help you quit. Smoking raises your risk of serious lung damage and lung cancer.
• Get medical care for other health conditions that can make your lung damage worse.

If you have serious trouble breathing, call 9-1-1 immediately.

Take care of your mental health

If you have an ILD, you may worry about your lung damage and symptoms getting worse. You may also feel depressed and have trouble adjusting to your new lifestyle changes, such as using oxygen therapy.

There are a number of ways to take care of your mental health.

• Talk about how you feel with your healthcare provider. Talking to a professional counselor or joining a patient support group also can help.
• Let your loved ones know how you feel and what they can do to help you. Support from family and friends can help lower your stress and anxiety.
• Get treatment for depression. If you’re depressed, you may need medicines or other treatments that can improve your quality of life.

Know your options

Serious ILDs can lead to life-threatening complications. Palliative and hospice care may help people who have ILDs have a better quality of life with fewer symptoms. End-of-life care may also reduce the amount of time spent in the hospital.

There is no way to prevent ILDs that are caused by your genes.

You can prevent some ILDs by quitting smoking and avoiding substances in your environment or at work that can damage your lungs.