Fluid buildup in the ankles, known as peripheral edema, usually responds well to a combination of elevation, compression, movement, and dietary changes. In many cases, you can reduce mild to moderate swelling at home within a few days. Persistent or sudden swelling, especially in only one leg, can signal something more serious that needs medical attention.
Why Fluid Collects in Your Ankles
Gravity pulls fluid downward throughout the day, and your ankles sit at the lowest point of your body when you’re standing or sitting. Normally, your veins and lymphatic system push that fluid back up toward your heart. When something disrupts that process, fluid leaks into the surrounding tissue and pools around your ankles and feet.
The most common triggers are prolonged sitting or standing, high salt intake, and hot weather. But several medical conditions also cause ankle swelling. Chronic venous insufficiency occurs when the one-way valves in your leg veins weaken or become damaged, allowing blood to pool rather than flow upward. Congestive heart failure causes fluid backup because the heart can’t pump blood efficiently. Kidney disease lets fluid and salt accumulate in the blood, with swelling typically showing up in the legs and around the eyes.
Certain medications are another overlooked cause. Calcium channel blockers, a common class of blood pressure drugs, cause ankle swelling in 1 to 15% of patients depending on the specific type. If your swelling started around the same time as a new medication, that connection is worth raising with your prescriber.
Elevate Your Legs the Right Way
Elevation is the simplest and fastest way to move fluid out of your ankles. The key detail most people miss: your legs need to be above heart level, not just propped on a footstool. Lie on your back and stack pillows under your calves and ankles until they’re higher than your chest. Hold this position for about 15 minutes, and aim for three to four sessions per day.
If getting your legs that high isn’t practical, resting them on a coffee table or ottoman still helps by slowing the force of gravity pulling fluid downward. Even partial elevation is better than keeping your feet flat on the floor all day.
Use Compression Socks or Stockings
Compression socks apply graduated pressure to your lower legs, squeezing fluid upward toward your heart and preventing it from settling around your ankles. They come in different pressure levels measured in millimeters of mercury (mmHg), and choosing the right level matters.
- 8 to 15 mmHg (mild): Good for everyday prevention if you sit or stand for long stretches. These are available over the counter and comfortable enough for all-day wear.
- 15 to 20 mmHg (moderate): Better for noticeable swelling from desk jobs, travel, pregnancy, or mild varicose veins.
- 20 to 30 mmHg (firm): The lowest level considered medical-grade. Often recommended after surgery or for moderate varicose veins.
- 30 mmHg and above: These require a prescription and are reserved for chronic venous insufficiency or severe swelling.
Put compression socks on first thing in the morning, before swelling has a chance to develop. They’re much harder to pull on once your ankles are already puffy.
Move Your Ankles Throughout the Day
Your calf muscles act as a pump for your veins, pushing blood and fluid upward each time they contract. Sitting or standing still for hours shuts that pump off. Even small, repetitive ankle movements can restart it.
Ankle pumps are the go-to exercise. Sit or lie with your legs extended, then point your toes toward your knees as far as you can, and then away from you as far as you can. Alternate back and forth for two to three minutes, and repeat this two to three times per hour. You can do these at your desk, on a plane, or in bed.
Ankle circles also help. Rotate one ankle clockwise 10 times, then counterclockwise 10 times, and switch to the other foot. Another option is heel-and-toe raises while seated: with your feet flat on the floor, lift your toes up toward the ceiling while keeping your heels down, then press your toes into the floor and lift your heels. Repeat 10 times. These exercises are simple enough to work into any routine and genuinely effective at pushing fluid out of the lower legs.
Walking, swimming, and cycling all engage the calf pump more aggressively. If your swelling is chronic, building regular lower-body movement into your week makes a noticeable difference over time.
Cut Back on Sodium
Salt makes your body hold onto water. The more sodium you consume, the more fluid your kidneys retain, and that extra fluid tends to collect in your ankles and feet. The federal dietary guidelines recommend staying under 2,300 milligrams of sodium per day, which is roughly one teaspoon of table salt.
Most excess sodium doesn’t come from the salt shaker. It hides in processed and packaged foods: canned soups, deli meats, frozen meals, bread, sauces, and restaurant dishes. Reading nutrition labels and cooking more meals at home are the two most effective ways to bring your intake down. If your ankle swelling is a recurring problem, tracking sodium for a week or two often reveals surprising sources.
When Medication May Be Needed
If home strategies aren’t enough, a doctor may prescribe diuretics, commonly called water pills. These work by signaling your kidneys to release extra salt and water into your urine, which reduces the total volume of fluid in your body. There are different types that act on different parts of the kidneys, and the choice depends on what’s causing your swelling and how your kidneys are functioning.
Diuretics treat the symptom, not necessarily the root cause. If your edema stems from heart failure, venous insufficiency, or kidney disease, you’ll likely need treatment for that underlying condition as well. Swelling that keeps coming back despite elevation, compression, and salt reduction is a signal that something deeper is going on.
How to Tell If It’s Something Serious
You can check the severity of your swelling at home with a simple test. Press your thumb firmly into the swollen area for a few seconds, then release. If it leaves an indentation that bounces back immediately with only a shallow dent (about 2 mm), that’s mild, grade 1 edema. If the pit is deeper (5 to 8 mm) and takes 15 seconds to several minutes to refill, you’re in grade 3 or 4 territory, and that warrants medical evaluation.
The biggest red flag is sudden swelling in only one leg, particularly when it comes with pain or cramping in the calf, skin that looks red or purple, and a feeling of warmth in the affected leg. This pattern suggests a possible deep vein thrombosis (DVT), a blood clot in a deep vein. DVT itself is treatable, but if the clot breaks loose and travels to the lungs, it becomes a pulmonary embolism. Signs of that include sudden shortness of breath, chest pain that worsens when you breathe deeply, a rapid pulse, dizziness, or coughing up blood. That’s an emergency.
Swelling that develops gradually in both ankles and responds to elevation is far less alarming, but if it persists for more than a few weeks or worsens despite the strategies above, it’s worth getting checked for an underlying cause like venous insufficiency, heart problems, or kidney issues.