Respiratory conditions

Idiopathic Pulmonary Fibrosis

Progressive scarring of the lung of unknown cause.

For patients & health professionals
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Authorship & review
Dr Sean James Ledger, BSc Physio (Hons) MSc PhD FHEA
Director and Principal Physiotherapist
Ahpra registration PHY0002298174
Version
1.0
Last updated
12 August 2026
Next review
12 August 2027
Every guide on this site is reviewed at least once a year, and sooner when the evidence changes.
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Part 1 · In plain language

Idiopathic pulmonary fibrosis (IPF) is a condition in which the lungs become progressively scarred and stiff for reasons that are not fully understood. The scarring makes it harder for oxygen to pass into the blood, causing worsening breathlessness and a dry cough. While the scarring cannot be reversed, antifibrotic medicines can slow it, and oxygen, pulmonary rehabilitation and staying active help with symptoms. Care also includes support and planning for the future. This page explains IPF and how it is managed.

IPF is a specific form of chronic progressive fibrosing interstitial pneumonia of unknown cause, occurring primarily in older adults, limited to the lungs, and associated with the histopathological and/or radiological pattern of usual interstitial pneumonia (UIP). It is distinct from other interstitial lung diseases and from progressive pulmonary fibrosis of known cause.

Definition

Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic, progressive fibrosing interstitial pneumonia of unknown cause, limited to the lungs and associated with the radiological and/or histological pattern of usual interstitial pneumonia (UIP). It occurs primarily in older adults and is characterised by progressive scarring (fibrosis) of the lung, worsening breathlessness and decline in lung function.1

Pathophysiology

Current concepts implicate repeated alveolar epithelial injury in a genetically and epigenetically predisposed older lung, with abnormal wound healing, fibroblast and myofibroblast accumulation, and progressive deposition of extracellular matrix. The result is destruction of normal lung architecture with honeycomb cysts and progressive loss of gas exchange.

Co-morbidities

Common co-morbidities include pulmonary hypertension, gastro-oesophageal reflux, obstructive sleep apnoea, coronary artery disease, emphysema (combined pulmonary fibrosis and emphysema syndrome), lung cancer, and anxiety and depression. Many of these are independent contributors to symptoms and prognosis.

Prevalence

IPF is uncommon but not rare. International prevalence estimates range from 2 to 29 per 100,000, increasing with age. It predominantly affects people over 60 years, with male predominance. Australian prevalence is likely similar; the Australasian Pulmonary Fibrosis Registry tracks national epidemiology.

Causes and risk factors

By definition the cause is unknown. Identified risk factors include older age, male sex, cigarette smoking, environmental and occupational exposures (metal dust, wood dust, silica, agriculture), chronic micro-aspiration, viral infections, and genetic factors (telomere-related gene mutations, surfactant protein mutations, MUC5B promoter polymorphism). A familial form is recognised.

Symptoms

Typical presentation is progressive exertional dyspnoea and a persistent dry cough in an older adult. Examination commonly reveals bilateral fine end-inspiratory “velcro” crackles, particularly at the bases, and digital clubbing in up to 50% of patients. The interval between symptom onset and diagnosis is often long, contributing to a substantial diagnostic delay.

Acute exacerbation of IPF

An acute exacerbation is an acute, clinically significant respiratory deterioration (within one month) with new bilateral ground-glass opacities or consolidation superimposed on a UIP pattern, not fully explained by cardiac failure or fluid overload. It carries a very high short-term mortality and warrants urgent specialist input.

Diagnosis

Importance of a diagnosis

Early and accurate diagnosis enables prompt initiation of antifibrotic therapy, referral for lung transplantation assessment, recognition and management of co-morbidities, advance care planning, and access to specialist multidisciplinary review and pulmonary fibrosis registries.

How is it diagnosed?

Diagnosis requires multidisciplinary integration of clinical, radiological, and (where needed) pathological data. Specifically: exclusion of other known causes of interstitial lung disease; the radiological or histopathological pattern of UIP; and, in many cases, multidisciplinary discussion at a specialist centre.

Radiology

HRCT is central. A definite UIP pattern shows subpleural, basal-predominant reticulation with honeycombing, with or without traction bronchiectasis, and absence of features suggesting an alternative diagnosis. Probable UIP and indeterminate patterns also exist and may require further investigation. HRCT alone is sufficient to diagnose IPF when the pattern is definite UIP and the clinical context is appropriate.

Lung function

Pulmonary function testing typically shows a restrictive pattern with reduced FVC and TLC, and reduced DLCO. Many patients have disproportionate reduction in DLCO relative to lung volumes, particularly when pulmonary hypertension or combined pulmonary fibrosis and emphysema co-exist. Six-minute walk testing is used for prognostication and to assess exertional desaturation.

Bronchoalveolar lavage and biopsy

BAL is used selectively to exclude alternative diagnoses (e.g. hypersensitivity pneumonitis). Surgical or transbronchial cryobiopsy may be needed when HRCT is non-diagnostic and the clinical context permits.

Investigations for secondary causes

Investigations to exclude other causes of fibrosing interstitial lung disease include detailed environmental and occupational history, autoimmune serology (ANA, ENA, RF, anti-CCP, myositis panel, ANCA), and consideration of hypersensitivity pneumonitis exposures. Connective tissue disease and chronic hypersensitivity pneumonitis are the principal alternative diagnoses to exclude.

Management

Management and goals

Goals are to: slow disease progression, manage symptoms (dyspnoea, cough, fatigue), maintain function and quality of life, identify and treat co-morbidities, provide timely access to lung transplantation assessment where appropriate, and integrate palliative and supportive care from diagnosis.

Treatment options

Modern management includes:2,3,4

Identifying an acute deterioration

Patients should be educated to recognise and report any acute worsening of breathlessness over hours to days, increased oxygen requirements, fever, or cough. Acute deterioration is an urgent reason for review and may represent an acute exacerbation, infection, pulmonary embolism, or cardiac decompensation.

Action plan

A written plan should specify usual symptoms, criteria for contacting the GP and the respiratory team, recognition of acute deterioration, and clearly documented patient preferences regarding hospitalisation and intubation. Advance care planning is a normal and important part of IPF care.

Medications

Medications for IPF

The two PBS-listed antifibrotic agents in Australia are:

Pirfenidone — taken orally three times daily with food; common adverse effects include nausea, fatigue, rash, and photosensitivity

Nintedanib — taken orally twice daily with food; common adverse effects include diarrhoea, nausea, transaminase elevation

Supplementary medications include cough suppressants (low-dose opioids when severe), PPIs (selectively), low-dose opioids for refractory dyspnoea in advanced disease, and treatment of co-morbidities.

Correct use of medications

Adherence to antifibrotics is challenging because of side-effects and the absence of perceived benefit. Active dose titration, anti-emetic support, sun protection (pirfenidone), and liver function monitoring (nintedanib) improve tolerability. Patients should be supported through the early months when side-effects are most common.

Order and timing

Antifibrotic medications are taken with food to reduce gastrointestinal side-effects. Oxygen, where prescribed, is used continuously (or for ≥15 hours per day if criteria met) and during exertion if exertional desaturation is significant.

Multi-system manifestations

Pulmonary hypertension

PH commonly complicates IPF, particularly in advanced disease, and contributes to disproportionate dyspnoea and reduced exercise capacity. Echocardiography and right heart catheterisation may be used to characterise it. Treatment is challenging and requires specialist input.5

GORD and aspiration

GORD is highly prevalent in IPF and may contribute to ongoing alveolar injury. Lifestyle and pharmacological treatment is reasonable in symptomatic patients; routine PPI in asymptomatic patients is no longer recommended.

OSA and other sleep-disordered breathing

OSA is common in IPF and contributes to fatigue and pulmonary hypertension. Sleep studies should be considered, particularly in symptomatic patients. CPAP can be challenging but provides benefit when tolerated.

Lung cancer

Lung cancer is more common in patients with IPF (relative risk 5–7-fold), particularly in those with combined pulmonary fibrosis and emphysema. Surveillance has not been formally established but should be considered, particularly in smokers.

Anxiety, depression and existential distress

Anxiety, depression, and existential distress are frequent and underestimated. Routine screening and proactive psychological and palliative support are essential.

Living with IPF

Staying active — why regular exercise matters

Breathlessness makes it tempting to rest and do less, but in IPF this sets off a deconditioning spiral: reduced activity weakens the muscles — especially the large muscles of the legs, such as the quadriceps — and weaker, less efficient muscles then bring on breathlessness at lower and lower levels of effort. Much of the day-to-day disability in IPF comes from this secondary loss of fitness and muscle, not from the lung scarring alone — which is exactly why it can be improved.6,7,8,9

Regular, ongoing physical activity and structured exercise are therefore essential, not optional. Pulmonary (cardiorespiratory) rehabilitation — combining aerobic exercise, lower-limb strength training, education and breathing techniques — improves walking distance, breathlessness and quality of life in IPF, and much of the benefit is lost if exercise stops. Activity should be maintained for life at a level tailored to you (with supplemental oxygen during exercise where needed), and continued gently through and after set-backs rather than abandoned. See Decreased exercise tolerance for how this cycle works and how to break it.

Nutrition

Maintenance of weight and muscle mass is important. Weight loss, sarcopenia, and frailty are associated with worse outcomes and reduced eligibility for transplantation. Dietitian input is recommended.

Sleep

Sleep is frequently disturbed by cough, breathlessness, and nocturnal hypoxaemia. Overnight oximetry should be considered. Sleep-disordered breathing should be actively screened for and treated.

Travel

Patients with significant IPF should be assessed for in-flight oxygen prior to air travel. Practical considerations include availability of oxygen at destination, mobility, and clinical letters confirming the diagnosis and supply needs.

Prognosis

Without antifibrotic therapy, median survival from diagnosis was historically 3–5 years, though wide individual variability exists. Antifibrotics slow decline but do not halt progression. Acute exacerbations and infections substantially worsen prognosis. Lung transplantation is the only intervention with the potential to extend survival in advanced disease.10

Anxiety, depression and advance care planning

The serious nature of the diagnosis warrants early and ongoing conversations about prognosis, treatment preferences, and end-of-life care. Integrating palliative care from diagnosis improves symptom control and quality of life and does not preclude active disease-modifying treatment.

Role of the physiotherapist

In IPF the physiotherapist focuses on preserving function and managing breathlessness rather than clearing sputum. They deliver pulmonary rehabilitation and prescribe ongoing exercise (with supplemental oxygen during activity where needed), teach breathing and pacing techniques and use of a handheld fan for refractory breathlessness, and provide education and support through a progressive illness, including a palliative approach alongside active treatment.

Warning signs

Call 000 nowSudden severe breathlessness at rest, blue or grey lips or fingertips, new confusion or drowsiness, or chest pain with breathlessness. Do not wait to see whether it settles.
Emergency department todayBreathlessness that has clearly worsened over days to a few weeks beyond your usual level, particularly with a new cough, fever or discoloured sputum, or oxygen levels lower than your usual readings. This pattern can indicate an acute exacerbation, which carries a high short-term risk and needs urgent specialist assessment.
Same-day medical assessmentA definite step down in what you can do, a change in your cough, needing more oxygen than usual, or new swelling of the ankles.

Part 1 · References

  1. Raghu G, Remy-Jardin M, Richeldi L, et al. Idiopathic pulmonary fibrosis (an update) and progressive pulmonary fibrosis in adults: an official ATS/ERS/JRS/ALAT clinical practice guideline. Am J Respir Crit Care Med 2022;205(9):e18–e47.
  2. King TE Jr, Bradford WZ, Castro-Bernardini S, et al. A phase 3 trial of pirfenidone in patients with idiopathic pulmonary fibrosis (ASCEND). N Engl J Med 2014;370(22):2083–2092.
  3. Richeldi L, du Bois RM, Raghu G, et al. Efficacy and safety of nintedanib in idiopathic pulmonary fibrosis (INPULSIS). N Engl J Med 2014;370(22):2071–2082.
  4. Birring SS, Kavanagh JE, Irwin RS, et al. Treatment of interstitial lung disease associated cough: CHEST guideline and expert panel report. Chest 2018;154(4):904–917.
  5. Waxman A, Restrepo-Jaramillo R, Thenappan T, et al. Inhaled treprostinil in pulmonary hypertension due to interstitial lung disease (INCREASE). N Engl J Med 2021;384(4):325–334.
  6. Dowman L, Hill CJ, May A, Holland AE. Pulmonary rehabilitation for interstitial lung disease. Cochrane Database Syst Rev 2021;(2):CD006322.
  7. Holland AE, Hill CJ, Conron M, Munro P, McDonald CF. Short term improvement in exercise capacity and symptoms following exercise training in interstitial lung disease. Thorax 2008;63(6):549–554.
  8. Dowman LM, McDonald CF, Hill CJ, et al. The evidence of benefits of exercise training in interstitial lung disease: a randomised controlled trial. Thorax 2017;72(7):610–619.
  9. Visca D, Mori L, Tsipouri V, et al. Effect of ambulatory oxygen on quality of life for patients with fibrotic lung disease (AmbOx): a prospective, open-label, mixed-method, crossover randomised controlled trial. Lancet Respir Med 2018;6(10):759–770.
  10. Kreuter M, Bendstrup E, Russell AM, et al. Palliative care in interstitial lung disease: living well. Lancet Respir Med 2017;5(12):968–980.

References are numbered in citation order (Vancouver/BMJ style) and were current at the time of writing. Guidelines are living documents — verify against the latest version before clinical use.

Drug pipelineFor the full therapeutic history, the approved agents and their pivotal trials, and what is in phase 2 and 3 now, see The IPF Drug Pipeline →
How we treat this at the clinic

Supervised exercise, breathing technique and self-management education are the mainstay of cardiorespiratory physiotherapy for this condition.

Cardiorespiratory Rehabilitation →
Part 2 of 2

Clinical evidence

Part 1 covers the same condition without the technical detail. What follows is the evidence base behind it, written for clinicians — the literature, the reasoning and the gaps.

For clinicians: this summary supports clinical reasoning and is not a protocol. Check current guidelines and local policy before applying it, and read it alongside the key references and guidelines directory.

Framing. Idiopathic pulmonary fibrosis is a progressive fibrosing disease in which antifibrotic therapy slows decline but does not reverse it, so symptom management, exercise capacity and timely transplant referral carry a large share of the clinical value.1 Physiotherapy sits squarely in that space: pulmonary rehabilitation has randomised support, and the physiotherapist frequently sees the functional decline before the next set of lung-function numbers does.

Disease-modifying and supportive therapy

  • Pirfenidone (ASCEND) and nintedanib (INPULSIS) both reduce the rate of forced vital capacity decline by roughly half; neither improves symptoms directly, and gastrointestinal side effects commonly limit adherence.2,3
  • The 2022 ATS/ERS/JRS/ALAT guideline conditionally recommends against long-term antacid therapy and against anti-reflux surgery for IPF alone, and emphasises multidisciplinary diagnosis and early transplant discussion.1
  • Inhaled treprostinil improved six-minute walk distance in pulmonary hypertension associated with interstitial lung disease (INCREASE), the first positive trial in that group and a reason to ask whether disproportionate desaturation has been investigated.4
  • Acute exacerbations carry very high mortality and are a recognised, unpredictable event rather than simple progression — relevant to how quickly a functional decline should be escalated.1

Rehabilitation and oxygen

  • Pulmonary rehabilitation improves exercise capacity, dyspnoea and quality of life in interstitial lung disease, with the Cochrane review reporting consistent short-term benefit and clinically important gains in six-minute walk distance.5,6
  • Benefit attenuates over six to twelve months, and is greatest and most durable in those with less severe disease — an argument for referring early rather than at the point of decompensation.7
  • Ambulatory oxygen improved quality of life in fibrotic lung disease with exertional desaturation in the AmbOx crossover trial, and supplemental oxygen during training allows higher work rates in desaturating patients.8
  • Cough is a major, under-treated symptom in IPF, associated with worse quality of life and disease progression; non-pharmacological cough suppression techniques are the physiotherapy contribution.9
  • Breathlessness at the end of life responds to low-dose opioids and to non-pharmacological measures; early palliative involvement is recommended alongside, not instead of, active management.1,10

Physiotherapy implications

  • Refer to rehabilitation at diagnosis, not when the patient is severely limited — the window for meaningful gain closes as disease advances.7
  • Expect profound exertional desaturation and plan for it: interval training, supplemental oxygen where prescribed, and prescription by symptoms and recovery rather than a saturation target alone.8
  • Airway clearance has no routine role. IPF is not a secretion-retention disease; treat cough as a symptom to modulate rather than a mechanism to assist.9
  • Teach cough control and breathlessness management — suppression techniques, pacing, positioning, hand-held fan, anxiety management — because these are what patients report as most useful.9,10
  • Watch for the treatable companions: deconditioning, corticosteroid-related myopathy, reflux, obstructive sleep apnoea, depression and disproportionate pulmonary hypertension.4
  • Escalate a rapid step change in breathlessness, new resting hypoxaemia, or a fall in walking distance over weeks — consider acute exacerbation, infection, pulmonary embolism or heart failure.
  • Support the transplant pathway: maintaining conditioning, weight and function is part of remaining a candidate, and physiotherapy documentation contributes to the assessment.1

Clinical reasoning

  • A fall in exercise capacity often precedes measurable lung-function change; treat serial walk tests as monitoring data and report them.
  • Distinguish progression from a superimposed acute event — the timescale usually separates them, and the second is urgent.
  • Disproportionate desaturation, syncope or right-heart signs point to pulmonary hypertension and warrant specialist assessment.4
  • Honesty about trajectory is part of good rehabilitation here: goals should be framed around function, symptom control and what matters to the patient rather than restoring lost capacity.

Evidence gaps

  • Optimal rehabilitation content, intensity and maintenance strategy in fibrotic disease remain undefined, and durability beyond a few months is poor.5,7
  • Whether rehabilitation alters survival, hospitalisation or transplant outcomes is unknown.
  • Long-term oxygen therapy evidence in fibrotic disease is extrapolated largely from COPD populations.8
  • Non-pharmacological cough interventions have been tested in small trials only, despite cough being a dominant symptom.9
Drug pipelineFor the full therapeutic history, the approved agents and their pivotal trials, and what is in phase 2 and 3 now, see The IPF Drug Pipeline →

References for the clinical evidence summary

  1. Raghu G, Remy-Jardin M, Richeldi L, et al. Idiopathic pulmonary fibrosis (an update) and progressive pulmonary fibrosis in adults: an official ATS/ERS/JRS/ALAT clinical practice guideline. Am J Respir Crit Care Med 2022;205(9):e18–e47.
  2. King TE Jr, Bradford WZ, Castro-Bernardini S, et al. A phase 3 trial of pirfenidone in patients with idiopathic pulmonary fibrosis (ASCEND). N Engl J Med 2014;370(22):2083–2092.
  3. Richeldi L, du Bois RM, Raghu G, et al. Efficacy and safety of nintedanib in idiopathic pulmonary fibrosis (INPULSIS). N Engl J Med 2014;370(22):2071–2082.
  4. Waxman A, Restrepo-Jaramillo R, Thenappan T, et al. Inhaled treprostinil in pulmonary hypertension due to interstitial lung disease (INCREASE). N Engl J Med 2021;384(4):325–334.
  5. Dowman L, Hill CJ, May A, Holland AE. Pulmonary rehabilitation for interstitial lung disease. Cochrane Database Syst Rev 2021;(2):CD006322.
  6. Holland AE, Hill CJ, Conron M, Munro P, McDonald CF. Short term improvement in exercise capacity and symptoms following exercise training in interstitial lung disease. Thorax 2008;63(6):549–554.
  7. Dowman LM, McDonald CF, Hill CJ, et al. The evidence of benefits of exercise training in interstitial lung disease: a randomised controlled trial. Thorax 2017;72(7):610–619.
  8. Visca D, Mori L, Tsipouri V, et al. Effect of ambulatory oxygen on quality of life for patients with fibrotic lung disease (AmbOx): a prospective, open-label, mixed-method, crossover randomised controlled trial. Lancet Respir Med 2018;6(10):759–770.
  9. Birring SS, Kavanagh JE, Irwin RS, et al. Treatment of interstitial lung disease associated cough: CHEST guideline and expert panel report. Chest 2018;154(4):904–917.
  10. Kreuter M, Bendstrup E, Russell AM, et al. Palliative care in interstitial lung disease: living well. Lancet Respir Med 2017;5(12):968–980.
Important: This page is general information, not medical advice. If your breathing or symptoms change suddenly or severely, seek urgent medical care. For personalised assessment, contact Inspire Clinic.

Corrections: If something on this page is wrong, out of date or unclear, we want to know. Email reception@inspireclinic.au with the page name and what you believe is incorrect. Substantive corrections are made promptly, and the guide’s version and last-updated date are changed to reflect it.