Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Collapsed Lung

A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a total collapse, it is called pneumothorax. If only part of the lung is affected, it is called atelectasis.

Causes of a collapsed lung include:

  • Lung diseases such as pneumonia or lung cancer
  • Being on a breathing machine
  • Surgery on the chest or abdomen
  • A blocked airway

If only a small area of the lung is affected, you may not have symptoms. If a large area is affected, you may feel short of breath and have a rapid heart rate.

A chest x-ray can tell if you have it. Treatment depends on the underlying cause.

It sits within Lungs and Breathing.

The lead U.S. institute for this subject is the National Heart, Lung, and Blood Institute.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Collapsed Lung

586 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

Start Here

  • AtelectasisMayo Foundation for Medical Education and Research
  • PneumothoraxMayo Foundation for Medical Education and Research

Diagnosis and Tests

Treatments and Therapies

Living With

Related Issues

Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Pulmonary Atelectasis, Pneumothorax. These are the terms to use when searching medical literature.


This page is built from the MedlinePlus health topic record for Collapsed Lung, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.