About idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a condition in which the lungs become scarred and breathing becomes increasingly difficult.

It's not clear what causes it, but it usually affects people around 70-75 years of age and is rare in people under 50.

Several treatments can help reduce the rate at which IPF gets worse, but there's currently no treatment that can stop or reverse the scarring of the lungs.

Symptoms of idiopathic pulmonary fibrosis

The symptoms of IPF tend to develop gradually and get slowly worse over time.

Symptoms can include:

  • shortness of breath
  • a persistent dry cough
  • tiredness
  • loss of appetite and weight loss
  • rounded and swollen fingertips (clubbed fingers)

Many people ignore their breathlessness at first and blame it on getting old or being out of shape. But eventually even light activity such as getting dressed can cause shortness of breath.

When to get medical advice

See your GP if you've struggled with your breathing for a while or have had a cough for more than three weeks.

These symptoms aren't normal and shouldn't be ignored.

If your GP thinks you could have a lung condition such as IPF, they can refer you to a hospital specialist for tests such as:

Read more about the tests for idiopathic pulmonary fibrosis.

Causes of idiopathic pulmonary fibrosis

In people with IPF, the tiny air sacs in the lungs (alveoli) become damaged and increasingly scarred. This causes the lungs to become stiff and means it's difficult for oxygen to get into the blood.

The reason this happens isn't clear. Idiopathic means the cause is unknown.

IPF has been linked to:

  • exposure to certain types of dust, such as metal or wood dust
  • viral infections
  • a family history of IPF – around 1 in 20 people with IPF has another family member with the condition
  • gastro-oesophageal reflux disease (GORD) 
  • smoking

But it's not known whether some of these factors directly cause IPF.

Treatments for idiopathic pulmonary fibrosis

There's currently no cure for IPF, but there are several treatments that can help relieve the symptoms and slow down its progression.

Treatments include:

  • self-care measures – such as stopping smoking, eating healthily and exercising regularly
  • medication to reduce the rate at which scarring worsens – such as pirfenidone and nintedanib
  • breathing oxygen through a mask – you can do this while you're at home and/or while you're out and about
  • pulmonary rehabilitation – exercises and advice to help you breathe more easily
  • lung transplant – this is suitable in a few cases, although donor lungs are rare

Read more about how idiopathic pulmonary fibrosis is treated.

Outlook for idiopathic pulmonary fibrosis

IPF gets worse over time, although the speed at which this happens is highly variable.

Some people respond well to treatment and remain relatively free of symptoms for many years, while others may get rapidly worse or find the breathlessness debilitating.

Other problems can also sometimes develop, including chest infections, pulmonary hypertension and heart failure.

It's very difficult to predict how long someone with IPF will survive at the time of diagnosis. Regular monitoring over time can indicate whether it's getting worse quickly or slowly.

Before the availability of specific treatments like pirfenidone and nintedanib about half of people with IPF lived at least three years from their diagnosis. Around 1 in 5 survived for more than five years.

It's hoped these figures will be improved by the availability of new treatments to slow the disease's progression.

Symptoms of idiopathic pulmonary fibrosis

The most common symptom of idiopathic pulmonary fibrosis (IPF) is shortness of breath, often when physically active, which can get worse over time.

At first, many people ignore their breathlessness (especially older patients) and blame it on getting old or being out of shape. But as the disease progresses and lung damage becomes more severe, even light activity like getting dressed or having a shower can cause breathlessness.

Other symptoms of pulmonary fibrosis include:

  • a persistent dry cough
  • tiredness
  • loss of appetite and weight loss

In up to half of all cases, there is also a change in the shape of the finger and toenails. This thickening of tissue at the base of the finger and toenails is known as digital clubbing. The exact cause of clubbing is unknown, but it can occur in people with various chest and heart diseases.

Secondary conditions

The strain IPF can place on your lungs and your heart can trigger a number of secondary conditions, outlined below.

Chest infection

You will have an increased risk of developing chest and airway infections such as:

Symptoms of a chest infection include:

  • worsening breathlessness
  • chest pain
  • a high temperature (fever) of 38C (100.4F) or above 
  • sweating and shivering

Pulmonary hypertension

Around a third of people with IPF will also go on to develop pulmonary hypertension. Pulmonary hypertension is when blood pressure inside the arteries connecting the lungs to the heart is dangerously high.

Symptoms of pulmonary hypertension include:

  • dizziness
  • feeling faint
  • chest pain (angina)
  • a racing heartbeat (tachycardia)

Read more about symptoms of pulmonary hypertension.

Heart failure

Heart failure, where the heart is unable to pump enough blood around the body, can develop when IPF becomes severe.

This is due to a combination of factors, including a build-up of blood in the right side of the heart (the side that pumps blood to the lungs), which develops because it is difficult to pump blood through the scarred lung tissue. The poor supply of oxygen from the diseased lungs to the heart muscle also contributes to heart failure.

Heart failure can cause various symptoms, including:

  • worsening breathlessness
  • extreme tiredness and weakness
  • swelling in the legs, ankles and feet (oedema) caused by a build-up of fluid

Read more about the symptoms of heart failure.

Causes of idiopathic pulmonary fibrosis

The exact cause of idiopathic pulmonary fibrosis (IPF) is not known. Idiopathic means having no known cause.

The current theory is that IPF is triggered when cells that line the lung alveoli (air sacs) become damaged by exposure to one of several substances or viruses.

The damaged cells try to repair themselves but the process becomes uncontrolled, resulting in thickening and scarring (fibrosis) of the alveoli and surrounding lung tissue. The amount of oxygen that can pass from the lungs into the blood is then significantly reduced.


A number of factors have been suggested as possible triggers for the initial damage to the cells lining the alveoli. Most experts agree that the two most significant risk factors are:

  • being a smoker or having smoked in the past
  • occupational exposure to certain types of dust – jobs that involve working with wood, metal, textile, stone, cattle or farming may increase the risk of IPF 

Other possible risk factors include:

  • viral infections – such as the Epstein-Barr virus or hepatitis C
  • gastro-oesophageal reflux disease (GORD) (where the acid from your stomach rises back up into your throat) – this may be accidentally inhaled into the lungs, causing damage to the alveoli
  • chronic aspiration – where food, drink or saliva enter the lungs and is not coughed back up, often due to a related condition
  • environmental pollutants or dust
  • genetic tendency – the condition appears to run in some families but this only seems to be the case in around 5% of people with IPF

As IPF is such a rare condition it is hard to estimate how much of an impact these risk factors can have on your chance of developing it.

Diagnosing idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) can be hard to diagnose because its symptoms are similar to other lung conditions, such as chronic obstructive pulmonary disease (COPD).

Your GP can refer you to hospital specialists for a number of tests to help rule out other conditions and confirm the diagnosis.

The checks and tests you may have include:

Medical history and examination

Breathing and blood tests

Chest X-ray and CT scan


Lung biopsy

Medical history and examination

Your doctor will ask about your medical history and whether there are other factors that could be causing a problem with your lungs, such as whether you:

  • smoke or have smoked in the past
  • have been exposed to harmful substances at work, such as asbestos
  • have other medical conditions

They may also:

  • check the sound of your breathing through a stethoscope – a crackling sound can suggest lung scarring (fibrosis)
  • look at your fingers to see if the ends are swollen (finger clubbing)
  • ask you to walk around for a few minutes to see if you become breathless

Breathing and blood tests

Lung function tests (also called pulmonary function tests) assess how well your lungs work and can help indicate what the problem may be.

These tests measure:

  • how quickly you can move air in and out of your lungs
  • how much air your lungs can hold
  • how well your lungs transfer oxygen into your blood and remove carbon dioxide from it (this can be checked using a blood test)

A commonly used lung function test is spirometry. During the test, you breathe into a mouthpiece that's attached to a monitor.

Chest X-ray and CT scan

A chest X-ray doesn't show the lungs in much detail, but it can help doctors spot some more obvious problems that could be causing your symptoms, such as cancer or a build-up of fluid.

If IPF is suspected, the chest x-ray will be followed by a computerised tomography (CT) scan

A CT scan is similar to an X-ray, but lots more images are taken and these are put together by a computer to create a more detailed image of your lungs.

This can help your doctor spot signs of scarring in your lungs.


If doctors still aren't sure what the problem is after the tests described above, they may suggest having a bronchoscopy.

This is a test where a narrow, flexible tube with a camera (bronchoscope) is passed down into your airways.

Your doctor can then look for anything abnormal and can take small tissue samples for testing.

You'll usually be awake for a bronchoscopy and it may cause coughing. Local anaesthetic will be used to numb your throat so it doesn't hurt and you may also be given a sedative injection which will make you feel sleepy during the procedure.

Lung biopsy

If other tests aren't conclusive, a lung biopsy may need to be carried out.

This involves keyhole surgery to remove a small sample of lung tissue so it can be analysed for signs of scarring.

The procedure is performed under a general anaesthetic (where you're asleep). Your surgeon makes several small incisions (cuts) in your side and an endoscope (a thin tube with a camera and a light at the end) is inserted into the area between the lungs and the chest wall.

The surgeon can see the lung tissue through the endoscope and is able obtain a small sample.

Treating idiopathic pulmonary fibrosis

There's currently no cure for idiopathic pulmonary fibrosis (IPF). The main aim of treatment is to relieve the symptoms as much as possible and slow down its progression.

The main treatments are:



Oxygen support

Pulmonary rehabilitation

Lung transplant

As the condition becomes more advanced, end of life (palliative) care will be offered.


There are several things you can do to stay as healthy as possible if you have IPF.

These include:


There are two medications that can help slow down the progression of IPF in some people: pirfenidone and nintedanib.

Some people also take a medication called N-acetylcysteine, although its benefits are uncertain.


Pirfenidone helps to slow the development of scarring in the lungs by reducing the activity of the immune system. It's normally taken as capsules three times a day.

It's recommended if breathing tests have shown your lung capacity is 50-80% of what would normally be expected.

If your condition gets worse despite taking pirfenidone and your lung capacity falls by 10% or more within a year, the medication will usually be stopped.

Side effects of pirfenidone can include:

For further information see, the National Institute for Health and Care Excellence (NICE) guidelines on pirfenidone for idiopathic pulmonary fibrosis.


Nintedanib is a newer medication that can also help slow down scarring of the lungs in some people with IPF. It's normally taken as capsules twice a day.

Like pirfenidone, it may be used if you have a lung capacity 50-80% of what would normally be expected and should be stopped if your lung capacity falls by 10% or more in a year while taking it.

Side effects of nintedanib can include:

For further information, see the NICE guidelines on nintedanib for idiopathic pulmonary fibrosis.


N-acetylcysteine is what's known as an antioxidant. It's available from many health shops and is usually taken as tablets.

There is some limited evidence to suggest it may reduce the amount of scar tissue in the lungs, although other studies have not shown any benefit.

If you're considering taking N-acetylcysteine, you should check with your specialist first as it may not be safe or suitable for everyone with IPF.

Oxygen support

IPF can cause levels of oxygen in your blood fall, which can make you feel more breathless.

If this happens, oxygen treatment can help with your breathing and allow you to be more active.

Oxygen is taken through nasal tubes or a mask attached to a small machine. This device provides a much higher level of oxygen than the air. The tubes from the machine are long, so you'll be able to move around your home while connected.

Read further about home oxygen treatment.

Portable oxygen devices that you can use while you're out and about are also available.

Pulmonary rehabilitation

Pulmonary rehabilitation is used for many long-term lung conditions and aims to help patients come to terms with their condition, learn the best ways to deal with it and improve their ability to function on a daily basis without severe breathlessness.

Courses in pulmonary rehabilitation are usually held locally and may involve:

  • education about pulmonary fibrosis
  • physical activity
  • breathing exercises
  • advice on nutrition
  • psychological support
  • a social support network

Lung transplant

If your condition continues to get worse despite treatment, your specialist may recommend a lung transplant. The decision to have a transplant will be based on:

  • how bad your condition is
  • how quickly your condition is getting worse
  • your age and general health
  • how much your condition is likely to improve after a transplant
  • whether a donor lung is available

A lung transplant can significantly improve life expectancy in people with IPF, although it's a major procedure that puts a great strain on the body.

Few people with idiopathic pulmonary fibrosis are suitable candidates for a transplant and donor lungs are scarce.

Palliative care

If you're told there is nothing more that can be done to treat your IPF or you decide to decline treatment, your GP or care team will provide you with support and treatment to relieve your symptoms.

This is called palliative care.

You can choose to receive palliative care:

  • at home
  • in a care home
  • in hospital 
  • in a hospice

Your doctor or care team should work with you to establish a clear plan based on your wishes.

For further information see End of life care.

Last updated:
13 February 2023