Pleural Effusion | Symptoms and Treatments | MedStar Health

What is pleural effusion?

The pleural space around the lungs allows them to expand and is lined with a thin layer of tissue called the pleura. Pleural effusion is the build-up of extra fluid in the space that can put pressure on your lungs and make it difficult to breathe or cause a lung to collapse. It’s sometimes referred to as “water on the lungs.”


If you have pleural effusion, you may experience:

You may feel relief from some symptoms when sitting upright or standing.

What causes pleural effusion?

3d illustration of lungs

The cause of pleural effusion will affect the type of fluid build-up around the lungs, which is either a watery or protein-rich fluid. Some common causes of pleural effusion include:


Diagnosing pleural effusion is the first step to developing a treatment plan. Our specialists may recommend one or more diagnostic and imaging procedures to evaluate your condition.


Treatment will depend on the condition causing your pleural effusion and the amount of fluid in the pleural space.

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