Swollen ankles have numerous possible causes, some of which include pregnancy complications, injury, infection, blood clots, lymphedema and venous insufficiency, according to WebMD. Ankle swelling is common after excessive walking or standing, but swollen ankles that persist or accompany additional symptoms may indicate a potentially severe health issue. Swollen ankles can also be a symptom of heart, liver or kidney disease, or a side effect of certain medications.
Some foot and ankle swelling during pregnancy is normal, but severe or sudden swelling may indicate a serious complication known as preeclampsia, as stated by WebMD. This condition may occur after the 20th week of pregnancy and is often accompanied by other symptoms such as headaches, infrequent urination, nausea and abdominal pain. A sprained ankle is the most common injury that causes swelling, and treatment methods generally include rest, cold packs and compression bandages. If symptoms are severe or don't improve with conservative treatment, the patient should consult a doctor.
People with diabetic neuropathy, a problem with the nerves in the feet, are prone to foot infections. For people with diabetes, swelling in the feet or ankles can be a serious cause for concern.
Although not always serious, swelling of the ankles can also be a sign of a problem with the heart, liver or kidney, cautions WebMD. Kidney and liver malfunction can cause swelling due to fluid buildup in the ankles. Heart failure could lead to swollen ankles in the evening due to salt and water retention.
Many commonly used medications can cause swelling of the feet and ankles, according to WebMD. These include hormones, steroids, many blood pressure medications, antidepressants, non-steroidal anti-inflammatory drugs and diabetes medications.
Lymphedema, a collection of lymphatic fluid that may develop due to a problem with the lymph vessels, is a common complication of radiation therapy or lymph node removal due to cancer, according to WebMD. Patients who experience ankle swelling after cancer treatment should contact a doctor immediately. Foot and ankle swelling may also be an early sign of venous insufficiency, a condition in which blood cannot move easily from the legs to the heart. This causes fluid retention in the soft tissues of the legs, which can lead to infection and ulcers of skin.