What Is Edema?
“Edema” is the medical term for swelling. Body parts swell from injury or inflammation. It can affect a small area or the entire body. Medications, pregnancy, infections, and many other medical problems can cause edema.
Edema happens when your small blood vessels leak fluid into nearby tissues. That extra fluid builds up, which makes the tissue swell. It can happen almost anywhere in the body.
Types of Edema
Peripheral edema. This usually affects the legs, feet, and ankles, but it can also happen in the arms. It could be a sign of problems with your circulatory system, lymph nodes, or kidneys.
Pedal edema. This happens when fluid gathers in your feet and lower legs. It’s more common if you’re older or pregnant. It can make it harder to move around in part because you may not have as much feeling in your feet.
Causes of Edema
Things like a twisted ankle, a bee sting, or a skin infection will cause edema. In some cases, like an infection, this may be helpful. More fluid from your blood vessels puts more infection-fighting white blood cells in the swollen area.
Critical illness. Burns, life-threatening infections, or other critical illnesses can cause a reaction that allows fluid to leak into tissues almost everywhere. This can cause edema all over your body.
Head trauma, low blood sodium (called hyponatremia), high altitudes, brain tumors, and a block in fluid drainage in the brain (known as hydrocephalus) can cause cerebral edema. So can headaches, confusion, unconsciousness, and coma.
Medications. Many medicines can cause edema, including:
- NSAIDs (such as ibuprofen and naproxen)
- Calcium channel blockers
- Corticosteroids (like prednisone and methylprednisolone)
- Pioglitazone and rosiglitazone
- Pramipexole
When they cause swelling, usually it’s mild leg edema.
Symptoms of Edema
Your symptoms will depend on the amount of swelling you have and where you have it.
Edema in a small area from an infection or inflammation (like a mosquito bite) may cause no symptoms. On the other hand, a large allergic reaction (such as from a bee sting) may cause edema on your entire arm that can bring pain and limit your arm’s movement.
Food allergies and allergic reactions to medicine may cause tongue or throat edema. This can be life-threatening if it interferes with your breathing.
Leg edema can make the legs feel heavy. This can affect 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 and sometimes low oxygen levels in the blood. Some people with pulmonary edema may have a cough. There may be an indent or a “pit” that remains for a while after you push on the skin in some types of edema. This is called pitting edema. If the tissue springs back to its normal shape, it’s called non-pitting edema. It’s a symptom that may help your doctor figure out the cause of your edema.
Treatment of Edema
To treat edema, you often must treat its underlying cause. For example, you might take allergy medications to treat swelling from allergies.
Edema from a block in fluid drainage can sometimes be treated by getting the drainage flowing again. A blood clot in the leg is treated with blood thinners. They break down the clot and get drainage back to normal. A tumor that blocks blood or lymph can sometimes be shrunk or removed with surgery, chemotherapy, or radiation.
Leg edema related to congestive heart failure or liver disease can be treated with a diuretic (sometimes called a ”water pill”) like furosemide (Lasix). When you can pee more, fluid from the legs can flow back into the blood. Limiting how much sodium you eat can also help.
