Edema means swelling caused by fluid in your body's tissues. It usually occurs in the feet, ankles and legs, but it can involve your entire body.

Causes of edema include

• Eating too much salt
• Sunburn
• Heart failure
• Kidney disease
• Liver problems from cirrhosis
• Pregnancy
• Problems with lymph nodes, especially after mastectomy
• Some medicines
• Standing or walking a lot when the weather is warm

To keep swelling down, your health care provider may recommend keeping your legs raised when sitting, wearing support stockings, limiting how much salt you eat, or taking a medicine called a diuretic - also called a water pill.

Edema is the accumulation of excess water in the tissues. It is most common in the soft tissues of the extremities. The physiological causes of edema include water leakage from blood capillaries. Edema is almost always caused by an underlying medical condition, by the use of certain therapeutic drugs, by pregnancy, by localized injury, or by an allergic reaction. In the limbs, the symptoms of edema include swelling of the subcutaneous tissues, an increase in the normal size of the limb, and stretched, tight skin. One quick way to check for subcutaneous edema localized in a limb is to press a finger into the suspected area. Edema is likely if the depression persists for several seconds after the finger is removed (which is called “pitting”).

Pulmonary edema is excess fluid in the air sacs of the lungs, a common symptom of heart and/or kidney failure. People with pulmonary edema likely will experience difficulty breathing, and they may experience chest pain. Pulmonary edema can be life threatening, because it compromises gas exchange in the lungs, and anyone having symptoms should immediately seek medical care.

In pulmonary edema resulting from heart failure, excessive leakage of water occurs because fluids get “backed up” in the pulmonary capillaries of the lungs, when the left ventricle of the heart is unable to pump sufficient blood into the systemic circulation. Because the left side of the heart is unable to pump out its normal volume of blood, the blood in the pulmonary circulation gets “backed up,” starting with the left atrium, then into the pulmonary veins, and then into pulmonary capillaries. The resulting increased hydrostatic pressure within pulmonary capillaries, as blood is still coming in from the pulmonary arteries, causes fluid to be pushed out of them and into lung tissues.

Other causes of edema include damage to blood vessels and/or lymphatic vessels, or a decrease in osmotic pressure in chronic and severe liver disease, where the liver is unable to manufacture plasma proteins (image). A decrease in the normal levels of plasma proteins results in a decrease of colloid osmotic pressure (which counterbalances the hydrostatic pressure) in the capillaries. This process causes loss of water from the blood to the surrounding tissues, resulting in edema.

Mild, transient edema of the feet and legs may be caused by sitting or standing in the same position for long periods of time, as in the work of a toll collector or a supermarket cashier. This is because deep veins in the lower limbs rely on skeletal muscle contractions to push on the veins and thus “pump” blood back to the heart. Otherwise, the venous blood pools in the lower limbs and can leak into surrounding tissues.

Medications that can result in edema include vasodilators, calcium channel blockers used to treat hypertension, non-steroidal anti-inflammatory drugs, estrogen therapies, and some diabetes medications. Underlying medical conditions that can contribute to edema include congestive heart failure, kidney damage and kidney disease, disorders that affect the veins of the legs, and cirrhosis and other liver disorders.

Therapy for edema usually focuses on elimination of the cause. Activities that can reduce the effects of the condition include appropriate exercises to keep the blood and lymph flowing through the affected areas. Other therapies include elevation of the affected part to assist drainage, massage and compression of the areas to move the fluid out of the tissues, and decreased salt intake to decrease sodium and water retention.

Edema means swelling. The condition called edema arises when part of the body becomes swollen because fluid gathers in the tissue. It most commonly affects the arms and legs. That is called peripheral edema.

Common early signs of peripheral edema include the following:

• An arm or leg starts feeling full or heavy.

• The arm or leg starts to look swollen.

• When you press the swelling, it leaves a dent.

• Your clothing or jewelry starts to feel tight and uncomfortable.

• The skin near the edema feels tight or warm.

• It becomes harder to move any joints that are affected.

• There is a sensation of tautness or even pain in the surrounding area.

Edema can have various causes. It is important to see a doctor and check what is causing it to make sure it gets treated correctly.

Edema can be:

• a mild and temporary water retention problem that goes away by itself,

• a symptom of a serious disease that needs treatment,

• a condition that could become chronic and severe (like lymphedema after cancer treatment or leg edema in one leg following deep vein thrombosis), or

• an adverse effect of medication or an allergic reaction.

General puffiness or swelling caused by water retention

Signs of this kind of edema include puffiness of the hands, feet and / or face. This kind of edema is temporary and goes away without treatment. It can happen because you have been standing or sitting for too long. Edema is common after a long flight, for example, or in people who have to stand for long periods at work. Many women experience edema during their monthly period (menstruation) or during pregnancy. Edema in pregnancy is usually harmless, although it can be a sign of other problems if blood pressure is also high.

Edema related to circulation (vascular), heart or liver problems

A variety of diseases can cause edema. Most of the time, the edema is not a serious illness, but it may be a sign for one. Here are some examples:

Venous insufficiency can cause edema in the feet and ankles, because the veins are having trouble transporting enough blood all the way to the feet and back to the heart. This means that it gathers in the legs, and fluid is forced out of the blood vessels into the surrounding tissue. Edema can also be caused by varicose veins.

Congestive heart failure can cause both peripheral edema and abdominal edema (ascites). This is because the heart is too weak to pump blood around the body properly, so the blood gathers in front of the heart. Because of this, and due to the increased blood pressure in the veins, fluid seeps out into the surrounding tissue. This may cause swelling in the legs or a build-up of fluid in the abdomen. If the person spends a lot of time lying down, the edema might show up on his or her back (called sacral edema). Congestive heart failure can also cause edema in the lungs (pulmonary edema). This is not common, but the condition is life-threatening. It means the lungs are filling with fluid because the left side of the heart is not strong enough to pump the blood returning from the lungs. The blood gathers in the blood vessels of the lung, and fluid seeps out into the lung tissue. The signs are shortness of breath and rapid, shallow breathing or coughing.

Kidney disease could cause edema in the legs and around the eyes, because when the kidneys do not remove enough sodium and water from the body, the pressure in the blood vessels starts building up, which can lead to edema.

Low protein levels in the blood: If there is a lack of the protein albumin in the blood, fluid can leak out of blood vessels more easily. Low protein in the blood can be caused by extreme malnutrition, as well as kidney and liver diseases which mean that the body loses too much or produces too little protein.

Liver diseases: Scarring of liver tissue (liver cirrhosis) due to, for instance, long-term alcohol abuse or a liver inflammation, can cause edema in the abdomen (called ascites). This is because cirrhosis causes a lack of proteins and congestion in the liver, which can lead to increased pressure in the blood vessels. As a result, fluid seeps out into the abdomen.

Severe lung conditions like emphysema can also cause edema in the legs and feet if the pressure in the lungs and heart gets very high.

Lymphedema

This is caused by damage to the lymphatic system. It usually affects only one part of the body, like an arm. The most common cause of lymphedema in countries like Germany is cancer treatment in which lymph nodes have been removed or destroyed. It could be temporary after cancer surgery, but it can also develop into a chronic condition that can become severe.

What Is Edema?

Edema, a condition in which fluid builds up in your body’s tissues, may be caused by some types of chemotherapy, certain cancers, and conditions not related to cancer.

What Are Signs of Edema?

Signs of edema may include:

• swelling in your feet, ankles, and legs
• swelling in your hands and arms
• swelling in your face or abdomen
• skin that is puffy, shiny, or looks slightly dented after being pressed
• shortness of breath, a cough, or irregular heartbeat

Tell your health care team if you notice swelling. Your doctor or nurse will determine what is causing your symptoms, advise you on steps to take, and may prescribe medicine.

Some problems related to edema are serious. Call your doctor or nurse if you feel short of breath, have a heartbeat that seems different or is not regular, have sudden swelling or swelling that is getting worse or is moving up your arms or legs, you gain weight quickly, or you don’t urinate at all or urinate only a little.

Ways to Prevent or Lessen Edema

Steps you can take to prevent or lessen edema-related swelling include:

• Get comfortable. Wear loose clothing and shoes that are not too tight. When you sit or lie down, raise your feet with a stool or pillows. Avoid crossing your legs when you sit. Talk with your health care team about wearing special stockings, sleeves, or gloves that help with circulation if your swelling is severe.
• Exercise. Moving the part of your body with edema can help. Your doctor may give you specific exercises, including walking, to improve circulation. However, you may be advised not to stand or walk too much at one time.
• Limit salt (sodium) in your diet. Avoid foods such as chips, bacon, ham, and canned soup. Check food labels for the sodium content. Don’t add salt or soy sauce to your food.
• Take your medicine. If your doctor prescribes a medicine called a diuretic, take it exactly as instructed. The medicine will help move the extra fluid and salt out of your body.

Talking with Your Health Care Team about Edema

Prepare for your visit by making a list of questions to ask. Consider adding these questions to your list:

• Are my medications or treatment likely to increase my risk of developing edema?
• Are there steps I can take to prevent edema?
• What symptoms or problems should I call you about?
• What steps can I take to feel better if I notice swelling?
• Are there foods, drinks, or activities I should avoid?

Swelling in the body can happen for many reasons. Summer heat can cause your arms or legs to swell if you’ve been sitting or standing for a while. Body parts can also swell from overuse or an injury. But sometimes, swelling is a sign of an underlying medical condition.

More than half your body is made of water. Much of it flows around in your bloodstream. Water also makes up a lesser-known fluid called lymph. Lymph travels through the lymphatic system, which is made up of the tissues and organs that produce, store, and carry immune cells.

When your body fluids build up in one place, it can lead to swelling. This is called edema. You can get edema anywhere in your body—your feet, legs, ankles, hands, or even face. It can appear in one place or in many body parts at the same time.

Sometimes it’s only temporary. Pregnancy can lead to swelling in the legs and ankles from the pressure of the baby. Eating too much salt can cause you to retain water. So can certain medications, like some used for high blood pressure.

“Edema can cause problems with moving around, discomfort, infections, and difficulty with wound healing,” says Dr. Dhruv Singhal, a surgeon who treats lymph system problems at Harvard University. “So any kind of swelling should be looked at by a health care provider.”

Edema may be a sign of a serious medical condition. A dangerous type of blood clot called a deep vein thrombosis, or DVT, can cause sudden edema. Heart, liver, or kidney problems can also lead to swelling.

In a disease called congestive heart failure, the heart has problems pumping blood around the body. This can cause fluid to pool in the legs. With liver or kidney damage, fluid can’t pass through them quickly and can build up in the limbs.

Trauma to the body can also trigger edema. Singhal treats a type of edema caused by damage to the lymphatic system. This is called lymphedema. In the U.S., lymphedema is most often caused by cancer surgery.

Treatment for edema depends on the cause. If the swelling is caused by a drug, switching to a different type of medication may help. People with edema caused by a blood clot usually receive a blood thinner to break up the clot. Drugs called diuretics may be used for conditions like heart failure. These help your body get rid of excess fluid.

“We also have certain treatments that almost all patients get, no matter what the cause of their edema is,” Singhal says. These include compression garments: stockings, sleeves, or gloves that help reduce swelling. They can help reduce discomfort even if the cause of edema is something that can’t be treated.

If you experience sudden swelling in one or more limbs, or minor swelling that’s getting worse over time, see a health care provider right away. Early treatment for many types of swelling can reduce symptoms in the long term, Singhal explains.

Living With Edema

Help reduce discomfort from swelling:

• Wear loose clothing and shoes that aren’t too tight. The exception is when your doctor recommends compression garments. These are meant to be tight.

• Prop up swollen legs. Raise your feet up when sitting or lying down if you have edema in your legs. Keep them above the level of your heart if you can.

• Exercise gently. Moving the part of your body with swelling can help with symptoms. Ask your health care provider for safe exercises to do.

• Limit salt in your diet. The sodium in salt can cause the body to retain fluid. Check food labels for sodium content.

• Take medications as prescribed. If your doctor prescribes medication for edema, take it exactly as instructed.