If the ankle swelling is new, you should always call your doctor about it.
You can retain fluid for many reasons. These include:
- Kidney problems
- Heart conditions
- Thyroid disorders
When only one ankle is swollen, the cause may be a blood clot or an ankle injury.
But the most common reason for swelling in both ankles is leaky valves in the leg veins. The leg veins return blood to the heart after the blood has delivered its oxygen and nutrients to the feet and lower legs. Unlike the arteries, the veins can't rely on the pumping action of the heart to move the blood in the right direction. The veins need the valves to stop blood from backing up.
Many people have malfunctioning vein valves that cause backpressure and fluid leak. Also, this problem leads to varicose veins.
In warmer weather, the tiny veins dilate and allow more than the usual fluid to leak into the surrounding tissues. Gravity pushes the fluid down toward the ankles. So standing for long periods in hot weather can make the ankles very swollen.
You can decrease the ankle swelling from leaky valves in the veins. Try:
- Wearing support hose
- Elevating your ankles above the level of your heart
- Cooling your feet
You should also eat less salt so that your body holds on to less water. Your doctor may prescribe a low-dose water pill (diuretic) if you still cannot control the swelling.