Swelling in the legs and feet--sometimes referred to as peripheral edema--is a condition caused by abnormal buildup of fluid in the limbs or inflammation and swelling of tissues or joints. While swelling in the lower extremities can be the result of relatively minor causes such as prolonged standing, it can also be a sign of a more serious underlying medical condition. If you have persistent or severe swelling in the legs and feet, contact your physician.
Common Causes
There are many common causes of swelling in the legs and feet. Increased age, standing on your feet for prolonged periods of time, being overweight or obese, or sitting for long periods, such as on a long airplane flight or car ride, can cause fluid to build up in the lower extremities, according to the University of Maryland Medical Center. Leg and foot edema is also common among pregnant women. Excessive swelling during pregnancy can be a sign of a serious medical condition known as preeclampsia, a condition that is dangerous to both the mother and unborn child in which the mother's blood pressure rises to abnormal levels, causing excess protein in her urine. If you are pregnant and have severe swelling in your lower body, arms, hands or face, contact your doctor as soon as possible for evaluation.
Inflammation and Immune System Dysfunction
According to the Mayo Clinic, swelling in the lower extremities can be caused by immune system responses that lead to inflammation. For example, rheumatoid arthritis--a chronic, inflammatory type of arthritis that commonly attacks the joints--is an autoimmune disorder that can cause swelling anywhere in the body.
Other types of arthritis such as gout, a form of arthritis that causes sudden, painful attacks on the joints, and osteoarthritis, a degenerative joint disease, can lead to fluid buildup due to inflammation. Certain injuries can also cause inflammation of tissues in the legs and feet that lead to swelling. For example, an Achilles tendon rupture, knee injury, knee bursitis, sprained ankle or a broken leg, ankle or foot can all cause peripheral edema.
Medications
Certain types of medications can increase the risk of swelling in the legs and feet. For example, nonsteroidal anti-inflammatory drugs such as ibuprofen can cause excess fluid to become trapped in leg tissues, according to the Mayo Clinic. Drugs containing testosterone and other hormones such as estrogen, delivered through birth control pills or hormone replacement therapy, can also cause fluid retention. Steroids and blood pressure medications called calcium channel blockers, including amlodipine, felodipine, verapamil, diltiazem and nifedipine, might also lead to peripheral edema, according to the University of Maryland Medical Center. Certain types of antidepressants such as MAO inhibitors, tranylcypromine and phenelzine, and tricyclic antidepressants, desipramine, nortriptyline and amitriptyline, are also known causes.
Serious Underlying Medical Conditions
Peripheral edema can sometimes be caused by a serious underlying medical condition. Blood clots, leg infections, a blockage of the lymph nodes in the legs called lymphatic obstruction, or heart, kidney or liver failure can all cause swelling of the feet and legs, according to the University of Maryland Medical Center. Venous insufficiency, a condition in which the legs cannot pump enough blood back to the heart, can also lead to fluid buildup in the lower extremities.
Other Causes
Varicose veins, enlarged and swollen veins that bulge beneath the skin's surface, can sometimes cause edema. Sunburn and other types of burns, insect bites and stings or dehydration and electrolyte imbalance caused by starvation or malnutrition may also lead to swelling in the legs and feet, according to the University of Maryland Medical Center. Surgeries on the legs or feet may lead to fluid buildup in the lower body as well.
