Pulmonary fibrosis is a condition that causes lung scarring and stiffness. This makes it difficult to breathe. It can prevent your body from getting enough oxygen and may eventually lead to respiratory failure, heart failure, or other complications.

Researchers currently believe that a combination of exposure to lung irritants like certain chemicals, smoking, and infections, along with genetics and immune system activity, play key roles in pulmonary fibrosis.

It was once thought that the condition was caused by inflammation. Now scientists believe that there is an abnormal healing process in the lungs that leads to scarring. The formation of significant lung scarring eventually becomes pulmonary fibrosis.

You may have pulmonary fibrosis for some time without any symptoms. Shortness of breath is typically the first symptom that develops.

Other symptoms can include:

  • dry, hacking cough that’s chronic (long term)
  • weakness
  • fatigue
  • curving of the fingernails, which is called clubbing
  • weight loss
  • chest discomfort

Since the condition generally affects older adults, early symptoms are often misattributed to age or a lack of exercise.

Your symptoms may seem minor at first and progress over time. The symptoms can vary from one person to another. Some people with pulmonary fibrosis become ill very quickly.

The causes of pulmonary fibrosis can be divided into several categories:

Autoimmune diseases

Autoimmune diseases cause your body’s immune system to attack itself. Autoimmune conditions that can lead to pulmonary fibrosis include:


The following types of infections may cause pulmonary fibrosis:

Environmental exposure

Exposure to things in the environment or workplace can also contribute to pulmonary fibrosis. For example, cigarette smoke contains many chemicals that can damage your lungs and lead to this condition.

Other things that can damage your lungs include:

  • asbestos fibers
  • grain dust
  • silica dust
  • certain gases
  • radiation


Some medications may also raise your risk of developing pulmonary fibrosis. If you take one of these medications on a regular basis, you may require close monitoring by your doctor.

  • chemotherapy drugs, such as cyclophosphamide
  • antibiotics, such as nitrofurantoin (Macrobid) and sulfasalazine (Azulfidine)
  • cardiac drugs, such as amiodarone (Nexterone)
  • biologic medications such as adalimumab (Humira) or etanercept (Enbrel)


In many cases, the exact cause of pulmonary fibrosis in unknown. When this is the case, the condition is called idiopathic pulmonary fibrosis (IPF).

According to the American Lung Association, most people with pulmonary fibrosis have IPF.


According to the Pulmonary Fibrosis Foundation, about 3 to 20 percent of people with IPF have another family member with pulmonary fibrosis. In these cases, it’s known as familial pulmonary fibrosis or familial interstitial pneumonia.

Researchers have linked some genes to the condition, and research about what role genetics plays is ongoing.

You’re more likely to be diagnosed with pulmonary fibrosis if you:

  • are male
  • are between the ages of 40 and 70
  • have a history of smoking
  • have a family history of the condition
  • have an autoimmune disorder associated with the condition
  • have taken certain medications associated with the disease
  • have undergone cancer treatments, particularly chest radiation
  • work in an occupation associated with increased risk, such as mining, farming, or construction

Pulmonary fibrosis is one of more than 200 types of lung diseases that exist. Because there are so many different types of lung diseases, your doctor may have difficulty identifying that pulmonary fibrosis is the cause of your symptoms.

In a survey by the Pulmonary Fibrosis Foundation, 55 percent of respondents reported being misdiagnosed at some point. The most common misdiagnoses were asthma, pneumonia, and bronchitis.

Using the most current guidelines, it’s estimated that 2 in 3 patients with pulmonary fibrosis can now be properly diagnosed without a biopsy.

By combining your clinical information and the results of a specific kind of CT scan of the chest, your doctor will be more likely to accurately diagnose you.

In cases when the diagnosis is unclear, a tissue sample, or biopsy, may be necessary.

There are several methods for performing a surgical lung biopsy, so your doctor will recommend which procedure is best for you.

Your doctor may also use a variety of other tools to diagnose pulmonary fibrosis or rule out other conditions. These may include:

  • pulse oximetry, a noninvasive test of your blood oxygen levels
  • blood tests to look for autoimmune diseases, infections, and anemia
  • an arterial blood gas test to more accurately assess the oxygen levels in your blood
  • a sputum sample to check for signs of infection
  • a pulmonary function test to measure your lung capacity
  • an echocardiogram or cardiac stress test to see if a heart problem is causing your symptoms

Your doctor can’t reverse the lung scarring, but they can prescribe treatments to help improve your breathing and to slow the progression of the disease.

The treatments below are some examples of current options used for managing pulmonary fibrosis:

  • supplemental oxygen
  • prednisone to suppress your immune system and reduce inflammation
  • azathioprine (Imuran) or mycophenolate (CellCept) to suppress your immune system
  • pirfenidone (Esbriet) or nintedanib (Ofev), antifibrotic drugs that block the scarring process in the lungs

Your doctor may also recommend pulmonary rehabilitation. This treatment involves a program of exercise, education, and support to help you learn how to breathe more easily.

Your doctor may also encourage you to make changes to your lifestyle. These changes may include the following:

  • You should avoid secondhand smoke and take steps to quit if you smoke. This can help slow the disease’s progression and ease your breathing.
  • Eat a well-balanced diet.
  • Follow an exercise plan developed with your doctor’s guidance.
  • Get adequate rest and avoid excess stress.

A lung transplant may be recommended for those under the age of 65 with severe disease.

The rate at which pulmonary fibrosis scars people’s lungs varies. The scarring isn’t reversible, but your doctor can recommend treatments to reduce the rate at which your condition progresses.

The condition can cause a number of complications, including respiratory failure. This happens when your lungs no longer work properly and they can’t get enough oxygen to your blood.

Pulmonary fibrosis also raises your risk of lung cancer.

Some cases of pulmonary fibrosis may not be preventable. Other cases are linked to environmental and behavioral risk factors that can be controlled. Follow these tips to lower your risk of getting the disease:

  • Avoid smoking.
  • Avoid secondhand smoke.
  • Wear a face mask or other breathing device if you work in an environment with harmful chemicals.

If you’re having trouble breathing, make an appointment with your doctor. Early diagnosis and treatment can improve the long-term outlook for people with many lung diseases, including pulmonary fibrosis.