Swollen legs and ankles usually respond well to a few straightforward strategies: elevating your legs above heart level, reducing salt intake, staying active, and wearing compression stockings. These steps work because most everyday swelling is caused by fluid pooling in your lower limbs due to gravity, prolonged sitting or standing, or excess sodium in your diet. But swelling can also signal something more serious, so knowing when to act at home and when to seek help matters.
Why Legs and Ankles Swell
Swelling happens when fluid leaks out of your blood vessels and collects in the surrounding tissue. Five things can cause that: too much pressure inside your blood vessels, too little protein in your blood to pull fluid back in, leaky vessel walls, blocked lymph drainage, or a combination of these. The most common culprit for chronic swelling in both legs is venous insufficiency, where the valves in your leg veins weaken and let blood pool downward instead of flowing back to your heart.
Other causes include heart failure, kidney disease, liver disease, sleep apnea, pregnancy, and certain medications. Blood pressure drugs, anti-inflammatory painkillers, and hormones (including some birth control) are frequent offenders. Swelling that gets worse after long periods of standing typically points to a vein-related problem, while swelling paired with shortness of breath or difficulty breathing while lying flat suggests the heart may be involved.
If only one leg is swollen, the concern shifts. A single swollen leg can mean a blood clot (deep vein thrombosis), lymphedema, or even a structural issue like compression of the left iliac vein by an overlying artery, a condition called May-Thurner syndrome.
Elevate Your Legs Correctly
Elevation is the simplest and most effective first step. The key detail most people miss: your legs need to be above the level of your heart, not just propped on an ottoman. Lying on your back with your legs resting on a stack of pillows, or on a wedge cushion, lets gravity work in your favor and encourages fluid to drain back toward your core. Aim for 20 to 30 minutes at a time, several times a day. If you work at a desk, even short elevation breaks during lunch or in the evening can make a noticeable difference.
Move Your Legs Regularly
Your calf muscles act as a pump for your veins. Every time they contract, they squeeze blood upward toward your heart. Sitting or standing still for hours shuts that pump off, and fluid accumulates.
Ankle pumps are one of the easiest exercises to fight this. While sitting or lying down with your legs extended, point your toes toward your knees, then away from you, alternating back and forth for two to three minutes. Repeat this two to three times per hour when you’re sedentary. Walking, swimming, and cycling also activate the calf pump effectively. Even short walks throughout the day are more useful than one long walk followed by hours of sitting.
Cut Back on Sodium
Sodium makes your body hold onto water, and most of it comes from processed and restaurant food rather than the salt shaker. For people managing fluid retention, a practical target is no more than 2,000 milligrams of sodium per day. That’s roughly one teaspoon of table salt total, including what’s already in your food. For context, a single fast-food sandwich can contain 1,200 mg or more.
Reading nutrition labels becomes essential. Canned soups, deli meats, frozen meals, soy sauce, and many condiments are among the highest sodium sources. Cooking at home with fresh ingredients gives you the most control. Increasing your potassium intake through foods like bananas, sweet potatoes, and leafy greens can also help your kidneys excrete excess sodium, though this is worth discussing with a provider if you have kidney problems.
Use Compression Stockings
Compression stockings apply gentle, graduated pressure to your legs, tightest at the ankle and loosening as they go up. This helps push fluid back into your veins and prevents it from pooling. They come in different pressure levels measured in millimeters of mercury (mmHg), and the right level depends on the severity of your swelling.
- 15 to 20 mmHg (mild): Good for very early or minimal swelling, tired legs from travel, or long days on your feet. Available over the counter at most pharmacies.
- 20 to 30 mmHg (moderate): The most commonly prescribed level for mild to moderate swelling and venous insufficiency. This is the starting point for most people with persistent edema.
- 30 to 40 mmHg (firm): Used for more significant swelling, especially in the lower legs, or when moderate stockings aren’t controlling the problem. Typically requires a prescription or fitting.
- 40 to 50 mmHg and above: Reserved for severe cases after clinical assessment.
Put compression stockings on first thing in the morning, before swelling has a chance to build up. If you wait until afternoon, they’ll be harder to get on and less effective. Knee-high stockings work for most ankle and lower-leg swelling, while thigh-highs or full pantyhose styles may be needed for swelling that extends higher.
When Swelling Is an Emergency
Most leg swelling is manageable at home, but certain patterns demand immediate attention. A blood clot in the deep veins of your leg can break loose and travel to your lungs, a condition called pulmonary embolism that can be fatal. Warning signs include sudden shortness of breath, chest pain that worsens when you breathe deeply or cough, a rapid pulse, dizziness or fainting, and coughing up blood. If you experience any of these, especially alongside a newly swollen leg, call emergency services.
A single leg that becomes suddenly swollen, warm, red, or painful also warrants urgent medical evaluation, even without chest symptoms. Deep vein thrombosis is more likely after surgery, long flights, prolonged bed rest, pregnancy, or if you take hormonal medications.
How Doctors Assess Swelling Severity
When you visit a provider, they’ll likely press a finger into your shin for several seconds and watch what happens. If the pressure leaves an indentation that slowly fills back in, that’s called pitting edema, and it’s graded on a 0 to 4 scale. At grade 1, there’s slight visible swelling with a small pit. By grade 3 or 4, the swelling extends above the knee and the tissue is so waterlogged that pressing firmly can barely reach the bone.
Your provider will also ask about timing (did it come on suddenly or build over weeks?), whether it’s in one leg or both, and whether you have symptoms like breathlessness, weight gain, or reduced urine output. These details help distinguish between causes that are benign and those that require treatment for heart, kidney, or liver problems. Blood tests, an ultrasound of the leg veins, or an echocardiogram of the heart may follow depending on the clinical picture.
Medications That Reduce Fluid
If lifestyle measures aren’t enough, your doctor may prescribe a diuretic, commonly called a water pill. These medications work by telling your kidneys to release more salt and water into your urine, which lowers the volume of fluid your heart has to pump and reduces swelling. There are several types. Loop diuretics are the most potent and are preferred when kidney function is reduced. Thiazide diuretics are milder and often used for blood pressure control alongside fluid management. Potassium-sparing diuretics are sometimes added because other diuretics can deplete potassium, which your heart and muscles need.
Diuretics are effective but come with trade-offs. You’ll urinate more frequently, especially in the first few hours after taking them. Dehydration, low potassium, dizziness when standing, and muscle cramps are possible side effects. Your provider will typically monitor your kidney function and electrolytes with periodic blood work while you’re on these medications.
Protecting Your Skin
Chronically swollen legs stretch and thin the skin over time, making it vulnerable to cracking, infection, and a condition called stasis dermatitis, where the skin becomes red, itchy, and inflamed. Moisturizing daily with a fragrance-free cream helps maintain the skin barrier. Avoid scratching, even when the skin itches, because small breaks can let bacteria in and lead to cellulitis, a painful skin infection that spreads quickly and often requires antibiotics.
Check your lower legs and ankles regularly for color changes, open sores, or areas that feel unusually warm. Brownish discoloration around the ankles is a common sign of long-standing venous insufficiency and means the skin in that area is already compromised. Catching skin breakdown early prevents ulcers that can take weeks or months to heal.