Causes

Many factors — varying greatly in severity — can cause leg swelling.

Leg swelling related to fluid buildup

Leg swelling caused by the retention of fluid in leg tissues is known as peripheral edema. It can be caused by a problem with the venous circulation system, the lymphatic system or the kidneys.

Leg swelling isn't always a sign of a heart or circulation problem. You can have swelling due to fluid buildup simply from being overweight, being inactive, sitting or standing for a long time, or wearing tight stockings or jeans.

Factors related to fluid buildup include:

• Acute kidney failure
• Cardiomyopathy (problem with the heart muscle)
• Chemotherapy
• Chronic kidney disease
• Cirrhosis (scarring of the liver)
• Deep vein thrombosis (DVT) (DVT)
• Heart failure
• Hormone therapy
• Lymphedema (blockage in the lymph system)
• Nephrotic syndrome (damage to small filtering blood vessels in the kidneys)
• Obesity
• Pain relievers, such as ibuprofen (Advil, Motrin IB) or naproxen (Aleve)
• Pericarditis (inflammation of the tissue around the heart)
• Pregnancy
• Prescription medications, including some used for diabetes and high blood pressure
• Pulmonary hypertension
• Sitting for a long time, such as during airline flights
• Standing for a long time
• Thrombophlebitis (a blood clot that usually occurs in the leg)
• Venous insufficiency, chronic (leg veins with a problem returning blood to the heart)

Leg swelling related to inflammation

Leg swelling can also be caused by inflammation in leg joints or tissues — either a normal response to injury or disease or due to rheumatoid arthritis or another inflammatory disorder. You'll usually feel pain with inflammatory disorders.

Conditions that can contribute to inflammation in the leg include:

• Achilles tendon rupture
• ACL injury (tearing of the anterior cruciate ligament in your knee)
• Baker's cyst
• Broken ankle
• Broken foot
• Broken leg
• Burns
• Cellulitis (a skin infection)
• Knee bursitis (inflammation of fluid-filled sacs in the knee joint)
• Osteoarthritis (disease causing the breakdown of joints)
• Rheumatoid arthritis (inflammatory joint disease)
• Sprained ankle