Edema is the abnormal buildup of fluid in a part of the body, which can cause swelling and pain.
Some causes of edema include:
- Inactivity. Swelling of the ankles during a long airplane trip is an example of edema caused by inactivity.
- Diseases such as heart failure. If the left side of the heart is damaged, it can cause fluid to build up in the lungs (pulmonary edema).
- Blood clots that stop the flow of blood through a blood vessel. This causes blood to pool behind the clot.
- Infection. The body often fights an infection by increasing blood flow to the area, which can result in edema.
The treatment for edema depends on the cause.
Current as of: July 1, 2025