Edema is the medical term for swelling. It is a general response of the body to injury or inflammation. Edema can be isolated to a small area or affect the entire body. Medications, infections, pregnancy, and many medical problems can cause edema.
Edema results whenever small blood vessels become "leaky" and release fluid into nearby tissues. The extra fluid accumulates, causing the tissue to swell..
Edema symptoms depend on the amount of edema and the body part affected.
Edema in a small area from an infection or inflammation (such as a mosquito bite) may cause no symptoms at all. On the other hand, a large local allergic reaction (such as from a bee sting) may cause edema affecting the entire arm. Here, tense skin, pain, and limited movement can be symptoms of edema.
Food allergies may cause tongue or throat edema, which can be life-threatening if it interferes with breathing.
Leg edema of any cause can cause the legs to feel heavy and interfere with walking. In edema and heart disease, for example, the legs may easily weigh an extra 5 or 10 pounds each. Severe leg edema can interfere with blood flow, leading to ulcers on the skin.
Pulmonary edema causes shortness of breath, which can be accompanied by low oxygen levels in the blood. Some people with pulmonary edema may experience a cough with frothy sputum.
Treatment of edema often means treating the underlying cause of edema. For example, allergic reactions causing edema may be treated with antihistamines and corticosteroids.
Edema resulting from a blockage in fluid drainage can sometimes be treated by eliminating the obstruction:
A blood clot in the leg is treated with blood thinners, and the clot slowly breaks down; leg edema then resolves as fluid drainage improves.A tumor obstructing a blood vessel or lymph flow can sometimes be reduced in size or removed with surgery, chemotherapy, or radiation.
Leg edema related to congestive heart failure or liver disease can be treated with a diuretic (''water pill'') like furosemide (Lasix). When urine output increases, more fluid drains from the legs back into the blood. Maintaining a sodium-restricted diet will also help limit fluid retention associated with heart failure or liver disease.