There are various causes of swollen ankles, including injury, edema, infection, and heart disease. Treatment depends on the underlying cause.

Generally swollen ankles can result from one of two things: edema or inflammation

The term edema means swelling due to the accumulation of excess fluid. It is particularly common in the lower leg, ankles, and feet.

Edema can occur from things like keeping the legs in the same position for too long, eating too much salt, and being at an unhealthy weight.

Certain conditions can also cause edema. They include:

  • various kidney problems
  • preeclampsia
  • blood clot
  • heart failure
  • chronic liver disease
  • malnutrition or malabsorption
  • hypothyroidism
  • varicose veins
  • infection

Inflammation, on the other hand, happens when a person’s immune system responds against an irritant. This can be acute or chronic.

This article examines 15 causes of ankle swelling, including conditions that can cause either edema or inflammation.

Chronic venous insufficiency (CVI) is a common cause of edema. CVI is a condition that typically affects the valves in the leg veins but may occur in other locations.

CVI can be painful and uncomfortable. It may also cause noticeable changes to the skin.

These valves usually make sure that blood flows toward the heart. In CVI, the valves malfunction and allow blood to flow backward and pool in the lower legs and ankles.

Sometimes, a blood clot, or thrombosis, can develop in one of the veins in the arm or leg. One type of blood clot is deep vein thrombosis (DVT), which requires urgent medical attention. A person can also get a superficial blood clot in the veins of the leg, which can progress into a DVT.

DVT obstructs the flow of blood returning to the heart, causing edema in the affected limb.

Sometimes, the body can compensate for the blockage by gradually diverting blood through smaller neighboring veins. Over time, these veins get larger and can drain blood from the limb.

If these veins do not increase in size, the limb may remain swollen. Persistent pain and swelling after a DVT is called post-thrombotic syndrome.

During pregnancy, the body produces more blood and bodily fluids to support the developing fetus.

Edema is a common side effect of pregnancy, especially in the third trimester. It can affect the ankles, feet, legs, face, and hands.

Slight swelling is common and usually harmless. However, sudden swelling of the hands and face could signify a potentially life-threatening condition called preeclampsia.

Preeclampsia is a life-threatening condition that can occur during the second or third trimester of pregnancy or up to 6 weeks after giving birth.

The condition involves dangerously high blood pressure and protein in the urine. It can cause various symptoms, including headaches, changes in vision, weight gain, and edema.

Preeclampsia that occurs during pregnancy can also affect the fetus.

Lymphedema is a swelling that affects the soft tissues in the arms or legs, including the ankles. It is due to a buildup of a fluid called lymph. This is mainly composed of white blood cells, which help fight infection.

Lymphedema occurs when there is a blockage or other damage to the lymphatic system. The lymphatic system is a network of tissues and organs that help rid the body of infection and keep fluids in balance.

Lymphedema can result from infections, cancer, and surgical removal of the lymph nodes. Some hereditary conditions can also cause lymphedema.

Heart failure occurs when the heart can no longer pump blood as effectively as it should.

In congestive heart failure, a reduction in blood flow out of the heart causes blood to back up into the veins. This may lead to edema, including in the legs and ankles.

Heart failure also affects the kidneys, reducing their ability to remove salt and water from the body. This further contributes to edema.

Chronic kidney disease is permanent kidney damage, which can worsen over time.

A person may not experience symptoms until they are in the late stages of the disease, called kidney failure or end-stage renal disease (ESRD).

During ESRD, the kidneys struggle to remove waste and extra fluid from the body. This can lead to a range of symptoms, including edema in the ankles.

A healthy liver produces a protein called albumin. Albumin prevents fluid from leaking out of the blood vessels and surrounding tissues.

Very low albumin levels due to liver disease can cause edema in the legs, ankles, and abdomen.

Hypothyroidism can affect a person’s muscles and joints, causing aches, pains, stiffness, and swelling.

If a person has hypothyroidism or an underactive thyroid, their thyroid gland produces too few hormones.

A 2017 study suggests there may be a link between thyroid disorders and rheumatoid arthritis, which can also cause painful edema in the joints.

Some medications can cause edema in the ankles as a side effect. Such medications include:

People who suspect their swollen ankle may be a side effect of medication may wish to talk with a doctor.

They may prescribe diuretic medications or suggest methods for reducing the swelling if it is uncomfortable.

Diabetes can make it difficult to regulate the sugar in the blood.

High blood sugar can damage the vessels that carry blood throughout the body, leading to poor circulation and edema in the lower legs.

Unmanaged edema from diabetes could ultimately lead to nerve damage.

People who sustain an injury to the foot or ankle may experience inflammation in that area, causing it to appear swollen.

Ankle sprains are common, accounting for up to 40% of sports-related injuries.

The American Academy of Orthopaedic Surgeons recommends the following home treatment for a sprained ankle:

  • resting
  • immediately applying ice wrapped in a thin piece of cloth
  • applying a compression wrap, bandage, or dressing
  • elevating the foot above heart level
  • taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, to ease the pain and reduce swelling
  • wearing a walking boot or brace to provide ankle support

Bacterial infections in the skin are called cellulitis. People with diabetes are particularly prone to this type of infection.

Cellulitis can cause various symptoms of inflammation, including redness, warm skin, and swelling that spreads rapidly. In rare cases, cellulitis can be life-threatening without treatment.

Bursitis is the inflammation of bursae, which are fluid-filled sacs that cushion joints. This condition is common in athletes and older adults, as well as those with occupations requiring lots of repetition.

The most commonly affected areas on the leg are the knee and ankle.

Learn more about ankle bursitis.

Arthritis can lead to inflammation that causes ankle swelling. Different types of arthritis can cause this, including:

Gout

Gout is a form of arthritis that causes swelling in joints close to the extremities, such as the ankles.

Gout occurs when uric acid builds up and forms crystals in the joints or surrounding tissues, resulting in inflammation.

Learn more about ankle gout.

Rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder causing fluid to accumulate in the lining of your joints, leading to swelling and causing potential lasting damage.

The ankle is a common area of inflammation in people living with RA.

When should you be worried about swollen ankles?

A person should contact a doctor if they have:

  • heat or discoloration in the swollen area
  • swelling that worsens or does not improve
  • a fever
  • a sudden increase in swelling during pregnancy
  • a history of heart, kidney, or liver disease

Many cases of edema, or swollen ankles, will resolve with proper home treatment.

How do you get rid of swollen ankles fast?

Depending on the cause, a person may need medical treatment to reduce ankle swelling. That said, there are some home remedies that might help as well. These include exercising your legs, reducing salt intake, wearing compression stockings or socks, wearing loose pants, and losing weight if needed.

Edema is an accumulation of fluid causing the swelling of certain parts of the body, usually the feet, ankles, and lower legs.

An ankle can swell for many reasons, such as trauma, an infection, cardiovascular issues, or pregnancy.