Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a serious chronic disease that affects the tissue surrounding the air sacs, or alveoli, in your lungs. This condition occurs when that lung tissue becomes thick and stiff for unknown reasons. Over time, these changes can cause permanent scarring in the lungs, called fibrosis, that make it progressively more difficult to breathe.

Your risk for IPF is higher if you smoke or have a family history of IPF, and the risk increases with age. The most common symptoms of IPF are shortness of breath and cough. Some people may not have symptoms at first, but signs and symptoms can develop and get worse as the disease progresses.

The way IPF advances varies from person to person, and scarring may happen slowly or quickly. In some people, the disease stays the same for years. In other people, the condition rapidly declines. Many people with IPF also experience what are known as acute exacerbations, where symptoms suddenly become much more severe. Other complications of IPF include pulmonary hypertension and respiratory failure, which happens when the lungs cannot deliver enough oxygen into the bloodstream without support. This prevents the brain and other organs from getting the oxygen they need.

There is currently no cure for IPF. However, certain medicines may slow the progression of IPF, which may extend the lifespan and improve the quality of life for people who have the disease.

Explore this Health Topic to learn more about IPF, our role in research and clinical trials to improve health, and where to find more information.

Causes - Idiopathic Pulmonary Fibrosis

IPF is a type of interstitial lung disease. It is caused by lung tissue becoming thick and stiff and eventually forming scar tissue within the lungs. The scarring, or fibrosis, seems to result from a cycle of damage and healing that occurs in the lungs. Over time, the healing process stops working correctly and scar tissue forms. What causes these changes in the first place is unknown.

To understand IPF it helps to understand How the Lungs Work. In IPF, the scarring makes it difficult to breathe and deliver oxygen from the lungs to the rest of the body. In healthy lungs, oxygen passes easily through the walls of the air sacs, called alveoli, into your capillaries and bloodstream. However, in IPF, the scarring makes the walls of the alveoli thicker. The thickened walls of the alveoli make it harder for oxygen to pass into the blood.

Figure A shows the location of the lungs and airways in the body. Figure B shows fibrosis, or scarring, in the lungs.
Figure A shows the location of the lungs and airways in the body. The inset image shows a detailed view of the lung's airways and air sacs in cross-section. Figure B shows fibrosis, or scarring, in the lungs. The inset image shows a detailed view of the fibrosis and how it changes the structure around the air sacs.

Look for
- Idiopathic Pulmonary Fibrosis

  • Risk Factors will discuss family history, lifestyle, or other environmental factors that increase your risk of developing IPF.
  • Treatment will discuss medicines, procedures, and lifestyle changes that your doctors may recommend if you are diagnosed with IPF.
  • Research for Your Health will discuss how we are using current research and advancing research to better understand and treat IPF.

Risk Factors - Idiopathic Pulmonary Fibrosis

You may have an increased risk for IPF because of your age, family history and genetic, lifestyle habits, or your sex.

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The risk of developing IPF increases as you age, and usually occurs in people older than 50. IPF is diagnosed most often in people who are in their 60s or 70s.

Family history and genetics
- Idiopathic Pulmonary Fibrosis

Your risk for IPF is higher if a first-degree relative, such as a parent or sibling, has IPF. The specific genes you inherit may make you more likely to develop IPF, especially if those genes contain certain changes, or mutations. To date, mutations in more than 10 different genes have been linked to an increased risk for IPF.

Your genes can put you at risk for IPF in a few ways.

Lifestyle habits
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Smoking is a common risk factor among people who have IPF.

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IPF is more common among men than women.

Screening and Prevention - Idiopathic Pulmonary Fibrosis

Currently, there are no screening methods to determine who may develop IPF. If you have certain risk factors, especially a family history of IPF, your doctor may recommend you have a pulmonary function test or an imaging test, such as a high-resolution chest CT scan, to look for scarring in the lungs.

Look for
- Idiopathic Pulmonary Fibrosis

  • Diagnosis will explain the questions, tests, and procedures that your doctor may use to diagnose IPF.
  • Living With will discuss what your doctor may recommend to prevent your IPF getting worse or leading to complications.
  • Research for Your Health will discuss how we are using current research and advancing research to better understand and treat IPF.
  • Participate in NHLBI Clinical Trials will discuss our open and enrolling clinical studies that are investigating prevention strategies for IPF.

Signs, Symptoms, and Complications - Idiopathic Pulmonary Fibrosis

The signs and symptoms of IPF develop over time. Symptoms may be different between people and may develop slowly or quickly.

Signs and symptoms
- Idiopathic Pulmonary Fibrosis

The most common signs and symptoms are:

  • Shortness of breath that gets worse over time. At first, you may be short of breath only during exercise. Over time, you may feel breathless even at rest.
  • A dry cough that gets worse. You may have repeated bouts of coughing that you cannot control.

Other signs and symptoms may include:

  • Aching muscles and joints
  • Clubbing, which is a widening and rounding of the tips of the fingers or toes
  • Fatigue
  • Gradual, unintended weight loss
  • Generally feeling unwell
  • Rapid, shallow breathing

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Complications of IPF may include the following:

Look for
- Idiopathic Pulmonary Fibrosis

  • Diagnosis will discuss tests and procedures used to detect signs of IPF and help rule out other conditions that may mimic IPF.
  • Treatment will explain treatment-related complications or side effects.
  • Living With will explain what to do if symptoms worsen or come back after treatment.

Diagnosis - Idiopathic Pulmonary Fibrosis

Your doctor will diagnose IPF based on your symptoms, your medical and family history, your risk factors, and the results from tests and procedures. Idiopathic means that your doctors cannot determine a cause of your disease at the time of diagnosis. They will rule out other medical reasons or conditions that may be causing your symptoms before diagnosing you with IPF. This may be done by doing other tests and talking to specialists.

Medical history and physical exam
- Idiopathic Pulmonary Fibrosis

To help determine whether you have IPF and rule out other possible causes of lung problems, your doctor may ask about your medical history and possible risk factors.

Your doctor may look for signs of IPF during a physical exam, such as:

  • Blue hands and feet from not enough oxygen in the blood
  • Clubbing of the fingers or toes
  • High-pitched crackles when listening to your lungs

Diagnostic tests and procedures
- Idiopathic Pulmonary Fibrosis

To diagnose IPF, your doctor may have you undergo some of the following tests and procedures.

  • High resolution chest CT scan, or HRCT, to take pictures of the inside of your lungs and look for scarring or inflammation. CT scans can also help distinguish between types of lung diseases. For IPF, doctors look for a pattern where the lungs look similar to a honeycomb.
  • Lung biopsy to see if your lung tissue shows signs of inflammation, scarring, or other changes. This procedure is sometimes used to verify the diagnosis of IPF. It usually is done by thoracoscopic surgery, in which small incisions are made and a small camera is used to direct surgical instruments.
  • Chest X-ray to take pictures of the lungs and look for evidence of inflammation or damage such as scarring. An X-ray does not provide as much detail as a high-resolution CT scan.

Tests for other medical conditions
- Idiopathic Pulmonary Fibrosis

Your doctor may perform some tests and procedures to help rule out other conditions that may cause lung disorders, including the following:

  • Blood tests, such as an antibodies test to look for signs of an autoimmune disease that can cause lung scarring.
  • Bronchoalveolar lavage (BAL) to look at the types of cells in your lung fluid. Sometimes it may be used when the types of cells can help distinguish between IPF and other lung diseases.
  • Pulmonary function tests to see if you show signs of reduced breathing capacity or abnormal blood oxygen levels. These tests help assess the severity of your lung disease, and they can help monitor whether your condition is stable or worsening over time.
  • Genetic testing, if you have a family history of interstitial lung disease or signs of early aging.

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  • Return to Risk Factors to review family history and genetics, lifestyle, or other environmental factors that increase your risk of developing IPF.
  • Return to Signs, Symptoms, and Complications to review common signs and symptoms of IPF.

Treatment - Idiopathic Pulmonary Fibrosis

There is currently no cure for IPF. Your doctor may recommend medicines, pulmonary rehabilitation, procedures, or other treatments to slow the progression of IPF and help improve your quality of life.

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Your doctor may recommend the following medicines:

  • Nintedanib or Pirfenidone to help slow the decline in lung function from IPF. They may also help to prevent an acute exacerbations, which is an unexpected and sudden worsening of symptoms over a period of days or weeks, and may prolong survival.
  • Antacids to help treat GERD. Treating GERD may help prevent acid from getting into the lungs from reflux, making IPF worse.

Other treatments
- Idiopathic Pulmonary Fibrosis

Your doctor may recommend other treatments to treat IPF, including:

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A lung transplant may be an option for some people who have advanced IPF. The major complications of a lung transplant are infection and rejection of the new organ by the body. You will have to take medicines for the rest of your life to reduce the risk of rejection following a lung transplant.

Look for
- Idiopathic Pulmonary Fibrosis

  • Research for Your Health will discuss how we are using current research and advancing research to better understand and treat people who have IPF.
  • Participate in NHLBI Clinical Trials will discuss our open and enrolling clinical studies that are investigating treatments for IPF.
  • Living With will explain what your doctor may recommend including life-long healthy lifestyle changes and medical care to prevent your condition from getting worse or to treat complications.

Living With - Idiopathic Pulmonary Fibrosis

If you have been diagnosed with IPF, it is important to continue your treatment plan. Talk to your doctor about how often to schedule follow-up care and how to monitor and understand your condition so you know when to get medical help. Your doctor may also recommend lifestyle changes and pulmonary rehabilitation to help you manage the disease.

It is important to know that the progression of IPF is different for each person and cannot be predicted. Managing your condition is best done with the help of a healthcare team that can help improve your quality of life.

Receive routine follow-up care
- Idiopathic Pulmonary Fibrosis

Regular checkups with your doctor may be part of your follow-up and treatment. Tell your doctor if you suddenly experience a worsening of symptoms over a period of days or weeks. This event is called an exacerbation. Sometimes a trigger or other factor may trigger it, but often there is no obvious cause. Exacerbations from IPF can be life threatening and are more common in advanced stages of IPF. People who have an exacerbation from IPF may have repeat episodes.

If your condition worsens, you may benefit from oxygen therapy full time. Some people who have IPF carry portable oxygen when they go out.

Return to Treatment to review possible treatment options for IPF.

Monitor your condition
- Idiopathic Pulmonary Fibrosis

Patients who have IPF can have other conditions as well, so it may be necessary to see multiple doctors who specialize in different areas of medical care.

Your doctor may use the following tests and procedures to monitor your condition, and also to determine whether to recommend a lung transplant.

  • Chest CT scan to look for lung cancer, or to see how you are responding to treatment or if your condition is getting worse.
  • Liver function tests to monitor possible side effects from medicines.
  • Pulmonary function tests, which your doctor may recommend every few months.

Adopt healthy lifestyle changes
- Idiopathic Pulmonary Fibrosis

Your doctor may recommend that you adopt healthy lifestyle changes to increase your overall health and prevent other conditions. This includes:

  • Quitting smoking. If you smoke, quit. Also, try to avoid other lung irritants, such as dust, chemicals, and secondhand smoke. Visit Smoking and Your Heart and the National Heart, Lung, and Blood Institute's Your Guide to a Healthy Heart. For free help quitting smoking, you may call the National Cancer Institute's Smoking Quitline at 1-877-44U-QUIT (1-877-448-7848).
  • Being physically active. Physical activity can help you maintain your strength and lung function and reduce stress. Try moderate exercise, such as walking or riding a stationary bike. Ask your doctor about using oxygen while exercising.
  • Aiming for a healthy weight
  • Heart-healthy eating. Also, eating smaller meals more often may relieve stomach fullness, which can make it hard to breathe.

Your doctor may recommend these lifestyle changes as part of a pulmonary rehabilitation program.

Take care of your mental health
- Idiopathic Pulmonary Fibrosis

Living with IPF may cause fear, anxiety, depression, and stress. Talking about how you feel with your healthcare team may help. Your doctor may recommend:

  • Counseling, particularly Cognitive behavioral therapy.
  • Medicines or other treatments, such as antidepressants, or other treatments that can improve your quality of life.
  • Joining a patient support group, which may help you adjust to living with IPF. You can see how other patients manage similar symptoms and their condition. Talk with your doctor about local support groups or check with an area medical center.
  • Getting support from family and friends, which can help relieve stress and anxiety. Let your loved ones know how you feel and what they can do to help you.
  • Discussing palliative care, if the disease becomes very advanced. For people who have severe symptoms from IPF, palliative care doctors may help them have a better quality of life with fewer symptoms.

Prevent exacerbations
- Idiopathic Pulmonary Fibrosis

To prevent exacerbations, your doctor may recommend avoiding situations where breathing is more difficult, such as in high altitudes, or when the air quality outside is poor from dust or pollution. Your doctor may treat exacerbations with medicines, such as glucocorticoids, or increased levels of supplemental oxygen.

Return to Signs, Symptoms, and Complications to review complications.

Research for Your Health

The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discovery to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote the prevention and treatment of heart, lung, blood, and sleep disorders including IPF. Learn about current and future NHLBI efforts to improve health through research and scientific discovery.

Improving health with current research
- Idiopathic Pulmonary Fibrosis

Learn about the following ways the NHLBI continues to translate current research into improved health for people with idiopathic pulmonary fibrosis. Research on this topic is part of NHLBI’s broader commitment to advancing lung diseases scientific discovery.

  • The IPF Clinical Research Network (IPFnet). The NHLBI formed IPFnet in 2005 to support research on IPF treatment. One study, PANTHER-IPF, found that a commonly used treatment for people who have IPF had potential to be harmful. The triple-medicine treatment included prednisone, azathioprine, and N-acetylcysteine. Guidelines for IPF now recommend against the three-medicine treatment, which is a change in clinical practice that has likely prevented unnecessary harm to other patients receiving care for IPF. Read more about this trial in Commonly used three-drug regimen for idiopathic pulmonary fibrosis found harmful.
  • NHLBI Workshop on Aging and Lung Disease Biology. The Division of Lung Diseases held a workshop in 2015 to discuss the intersection of aging and lung biology, including why cellular aging is linked with IPF. Participants identified research directions to advance our understanding and management of aging-related lung diseases, such as developing new animal models of IPF. Visit NHLBI Workshop on Intersection between Aging Biology and Pathobiology of Lung Diseases for more information.
  • NHLBI Workshop on Improving Targeted Medicine Delivery Methods in Lung Diseases. A 2014 workshop discussed lung biology and determined priorities for research funding in the development of better targeted treatments for lung diseases. Learn more about Targeted Drug Delivery for Lung Diseases.
  • NHLBI Workshop on Preventing Chronic Lung Diseases. The Division of Lung Diseases convened a 2013 workshop to discuss the current knowledge on preventing specific lung diseases and key areas for future research. Learn more about Prevention of Chronic Lung Diseases.
  • Advancing the Understanding of Lung Development. The Molecular Atlas of Lung Development Program (LungMAP) is integrating many datasets to build a molecular map of the developing lung in both humans and mice. The program is helping advance lung research, in part through its web-based data resource, called BREATH, which allows users to access LungMAP data and findings.
  • A Diabetes Drug That May Help Treat Lung Fibrosis. Research partially supported by the NHLBI recently found that the medicine metformin, which is already approved to treat type 2 diabetes, was effective at reversing lung fibrosis in a laboratory model of IPF. The findings support the need for future studies of metformin as an IPF treatment. Visit Diabetes drug could treat lung fibrosis for more information.
  • Certain Lung Cells May Cause Fibrosis. NHLBI-supported researchers found two groups of lung cell types that responded differently to injury. One cell type promoted regeneration of lung tissue, whereas the other cell type promoted scarring. This discovery may provide targets for new types of IPF treatments or medicines.
  • Discovering How Aging Cells Contribute to IPF. An NHLBI-supported study suggested that older cells in the lungs that cannot produce new lung tissue may contribute to the risk for or worsening of IPF. Other NHLBI-funded studies are revealing how certain genes that control the aging process of cells is associated with IPF.
  • Identifying Specific Genes That Increase Risk for IPF. NHLBI-supported research confirmed the association between a certain gene called MUC5B and IPF that greatly increases the risk of pulmonary fibrosis.

Advancing research for improved health
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In support of our mission, we are committed to advancing IPF research, in part through the following ways.

Participate in NHLBI Clinical Trials

We lead or sponsor many studies on idiopathic pulmonary fibrosis (IPF). See if you or someone you know is eligible to participate in our clinical trials.

Are you between 40 and 85 with worsening idiopathic pulmonary fibrosis?

This study aims to test a new combination treatment for acute exacerbations, a life-threatening complication of idiopathic pulmonary fibrosis (IPF) that has no approved treatment. The treatment is meant to help stop part of the immune system from further injuring the lung tissue. To participate in this study, you must be between 40 and 85 years old and have worsening IPF. This study is located in Birmingham, Alabama; Boston, Massachusetts; Philadelphia, Pennsylvania; and Pittsburgh, Pennsylvania.

Do you have a first-degree relative diagnosed with an interstitial lung disease?

This study aims to better understand how interstitial lung diseases develop, by looking at the lungs of people who are at risk for an ILD. Participants will undergo a computed tomography (CT) scan, and researchers will look for visual evidence of the disease in an early stage. To participate in this study, you must be at least 35 years old and have a first-degree relative with a clinical diagnosis of ILD or be at least 50 years old with a smoking history of at least one pack of cigarettes per day. This study is located in New York, New York.

Do you have short telomeres and a telomere gene mutation?

Some people who have aplastic anemia have very short telomeres, which protect the ends of DNA in chromosomes. This study is testing whether low doses of the medicine danazol help prevent telomeres from getting shorter and reduce signs of damage from aplastic anemia or related conditions. Participants in this study must be 3 years or older and have a telomere disease and signs of aplastic anemia, lung disease such as pulmonary fibrosis, or liver disease. This study is located in Bethesda, Maryland.

Are you an adult who has idiopathic pulmonary fibrosis or an advanced lung cancer?

This study aims to see whether a new imaging dye for positron emission tomography (PET) is effective at looking at fibrosis in lung cancer and idiopathic pulmonary fibrosis (IPF). Participants will be given the imaging dye and then receive a PET scan. To participate in this study, you must either be between 18 and 80 years old and have lung cancer or be a healthy volunteer or be between 50 and 80 years old and have IPF. This study is located in Boston, Massachusetts.

More Information

After reading our Idiopathic Pulmonary Fibrosis Health Topic, you may be interested in additional information found in the following resources.

NHLBI resources
- Idiopathic Pulmonary Fibrosis

Non-NHLBI resources
- Idiopathic Pulmonary Fibrosis


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