What compression stockings and pumps do, and when doctors prescribe them

Compression stockings and pumps are medical devices that squeeze your leg or arm to push blood back toward your heart. Doctors prescribe them when blood pools in your limbs—usually because veins are damaged, valves don't close properly, or your legs swell from fluid buildup. The pressure is measured in millimeters of mercury (mmHg), and the amount matters: too little does nothing, too much can cut off circulation.

Compression is most commonly used for venous insufficiency (when leg veins don't return blood efficiently), deep vein thrombosis (DVT, a blood clot), lymphedema (swelling from damaged lymph vessels), and post-thrombotic syndrome (lasting swelling and pain after a clot). It's also used after surgery or during long flights to prevent clots from forming. The goal is not to cure the underlying condition but to manage the symptoms and prevent complications like skin breakdown or another clot.

Key Takeaways

  • Compression stockings come in four pressure levels (mild, moderate, high, and extra-high), and your doctor must specify which one because wearing the wrong pressure can harm you.
  • Stockings work only if worn consistently—usually all day—and must fit properly; an ill-fitting stocking can cut off circulation instead of improving it.
  • Sequential pneumatic pumps (machines that inflate and deflate) are stronger than stockings and are typically used in a clinic or at home for lymphedema or severe swelling.
  • Compression is not safe for everyone: people with certain heart conditions, severe arterial disease, or skin infections should not use it without explicit medical approval.
  • Your doctor should check your leg arteries before prescribing compression, because restricting blood flow to a leg that already has poor arterial supply can cause tissue damage.

The four pressure levels and what each is used for

Compression stockings are labeled by the pressure they deliver at the ankle, measured in mmHg. Mild compression (8–15 mmHg) is available over the counter and is used for tired legs, minor swelling, or prevention during travel. Moderate compression (15–20 mmHg) requires a prescription in most places and treats mild to moderate venous insufficiency or lymphedema. High compression (20–30 mmHg) is prescribed for more severe swelling, post-thrombotic syndrome, or active DVT. Extra-high compression (30–40 mmHg or above) is reserved for severe lymphedema or venous ulcers and almost always requires professional fitting.

The pressure is strongest at the ankle and decreases as it moves up the leg—this graduated pattern is what makes compression work. If you wear the wrong pressure level, you can make swelling worse instead of better. A stocking that is too tight can act as a tourniquet and cut off blood flow; one that is too loose won't provide enough pressure to move fluid upward. This is why your doctor's recommendation matters and why proper fitting is essential.

How to put on and wear compression stockings correctly

Putting on compression stockings is harder than regular socks because the fabric is thick and tight. Most people find it easiest to put them on first thing in the morning, before the leg swells during the day. Sit down, smooth the stocking up your leg slowly, and make sure there are no wrinkles or bunched fabric—wrinkles create pressure points that can damage skin. If you have limited hand strength or mobility, a stocking aid (a plastic device that holds the stocking open) or donning gloves (rubber gloves that grip better) can help.

Wear your stockings for the full time your doctor recommends, which is usually all day and into the evening. Taking them off during the day defeats their purpose because swelling returns quickly. Wash them by hand in warm water with mild soap each night—machine washing and the dryer damage the elastic. Most stockings last three to six months with daily wear before the elastic weakens and they stop working. Check your skin each morning and evening for redness, blisters, or sores; compression can trap moisture and cause skin breakdown if not monitored.

Sequential pneumatic pumps and how they differ from stockings

A sequential pneumatic compression pump is a machine with an inflatable sleeve that wraps around your leg or arm. The pump inflates and deflates in a wave pattern, starting at your ankle or hand and moving upward, mimicking the muscle contractions that normally push blood and lymph. These machines are much more powerful than stockings and are typically used in a clinic or prescribed for home use when swelling is severe or stockings alone aren't working.

Pumps are the standard treatment for lymphedema because they can move fluid that stockings cannot. A typical session lasts 30 minutes to an hour, and your doctor will tell you how often to use it—usually once or twice daily. Some people use a pump at a clinic under supervision; others rent or own a machine for home use. Insurance may cover pumps if your doctor documents that stockings have failed or that you have lymphedema, though coverage varies by plan and state.

Pumps are not a replacement for stockings; most people use both. You wear the stocking during the day to maintain the improvement the pump created, and use the pump at home to reduce swelling further. Like stockings, pumps require proper fitting—the sleeve must be the right size and pressure, or it won't work and may cause harm.

Who should not use compression and what to check before starting

Compression is not safe for everyone. Do not use compression if you have severe arterial disease (narrowed arteries that limit blood flow to your leg), because squeezing the leg will cut off what little blood is reaching the tissues. People with acute DVT (a fresh clot) should not wear compression without a doctor's explicit approval, because the pressure could dislodge the clot. Compression is also unsafe for people with congestive heart failure that is not well controlled, because pushing fluid back to the heart can overload it.

Other conditions that require caution include severe diabetes with nerve damage (you may not feel skin damage), active skin infections or open wounds, and severe edema from kidney or liver disease. Before prescribing compression, your doctor should check the blood flow in your leg arteries using a simple ultrasound test called an ankle-brachial index (ABI). This test compares blood pressure in your ankle to blood pressure in your arm; if the ratio is very low, it means your arteries are too narrowed for compression to be safe.

Skin care and monitoring while using compression

Compression devices create a warm, moist environment under the fabric, which can lead to skin breakdown, fungal infections, or pressure sores if you don't monitor carefully. Check your skin every morning and evening for redness that doesn't fade within 30 minutes of removing the stocking, blisters, sores, or areas of numbness. If you have diabetes or nerve damage, inspect even more carefully because you may not feel pain from developing sores.

Wash your legs daily with soap and water, dry thoroughly between the toes and in skin folds, and apply lotion to prevent dry skin—but do not apply lotion right before putting on the stocking, as it makes the stocking slip. If you develop a rash, sore, or sign of infection, remove the stocking and contact your doctor before wearing it again. Do not try to treat a skin problem on your own while continuing to wear compression, because the device will trap bacteria and make the infection worse.

Cost, insurance coverage, and where to get fitted

Over-the-counter mild compression stockings cost $20 to $60 per pair and are available at pharmacies and online. Prescription-strength stockings cost $40 to $300 per pair depending on the pressure level and whether they are custom-made to your measurements. Most insurance plans cover prescription compression stockings if your doctor documents medical necessity, though you may need prior approval and the plan may limit how many pairs per year you can receive.

Pneumatic pumps cost $3,000 to $8,000 to purchase, but many people rent them for $200 to $400 per month. Insurance coverage for pumps is more restrictive and usually requires documentation that stockings have failed or that you have a diagnosis like lymphedema. Medicare covers pumps for certain conditions, but coverage rules vary by state and change frequently.

Get fitted by a medical professional—a nurse, physical therapist, or certified compression fitter—rather than guessing your size. Many hospitals, wound care clinics, and vascular surgery offices have fitting services. If your doctor prescribes compression, ask for a referral to a fitter; some insurance plans require fitting at a specific location in order to cover the cost.

Frequently Asked Questions

Can I wear compression stockings at night?

Most people should remove stockings at night to let skin breathe and to avoid skin breakdown from prolonged pressure. Your doctor may recommend wearing them all day and evening but removing them at night, or wearing them 24 hours if you have severe lymphedema. Ask your doctor for specific guidance based on your condition.

What if compression stockings make my leg hurt or turn blue?

Stop wearing them immediately and contact your doctor. Pain, bluish skin, or numbness means the stocking is too tight, is cutting off circulation, or is not the right size. Do not adjust the stocking yourself or try a different size without medical guidance.

Do compression stockings work if I only wear them sometimes?

No. Compression only works while you're wearing it, and swelling returns within hours of taking it off. Inconsistent use defeats the purpose and may frustrate you into stopping altogether. Consistency is more important than pressure level.

Can I use a compression pump instead of wearing stockings?

Pumps are more powerful but are not meant to replace stockings. Most treatment plans use both: the pump reduces swelling during a session, and the stocking maintains that improvement during the day. Using only a pump without a stocking will result in swelling returning between sessions.

Will compression cure my venous insufficiency or lymphedema?

No. Compression manages symptoms and prevents complications, but it does not repair damaged veins or restore lymph vessels. You will need to wear compression long-term, and your doctor may recommend other treatments like medications, procedures, or lifestyle changes to address the underlying cause.