A special stocking (a.k.a. tights) designed to treat and/or prevent disorders of the veins in the leg. Unlike the similar anti-embolism stockings, compression stockings are designed for use by ambulatory individuals.
They work together with the normal pump action of the leg to provide move blood flow in the deep veins, back towards the torso. This reduces swelling and discomfort. They may be knee-length or come all the way up the thigh. They come in various materials, mine are made with microfiber. The compression of the stocking is graduated, with the most pressure at the foot and ankle, to compress the surface arteries. This compression—squeezing—of the arteries of the foot and leg makes the blood pressure higher in the arteries, helping your blood to push back into the veins and return up the leg to the heart, even if the valves in the vein are damaged.
Light pressure compression stockings may be purchased over the counter. These are typically used by people whose jobs require them to be on their feet all day, to reduce discomfort. They may also be used on long flights to reduce the chance of deep venous thrombosis.
Higher pressure stockings require a prescription, because we can't have any random lunatic buying high compression graduated hosiery. It is best to visit an expert for measurement and sizing for fit. These stockings are typically prescribed after deep venous thrombosis or similar difficulties have occurred, followed by Postthrombotic syndrome (PTS). The higher pressure compensates for damage to the venous systems in the leg. I found that just a few days of wearing the high compression stocking reduced my PTS swelling to a relatively minimal amount, permitting me to don footwear and resume normal activities. (Mine are the 820 MIDTOWN MICROFIBER for MEN*, made by Sigvartis.)
The stocking is a bit awkward to put on because it is, of course, quite tight. Vendors sell a special tool called a ‘donner’ but I found that to be unnecessary. I simply put the sock onto my lower foot, bunching it at mid instep, and then haul like crazy on the top until it glides up my leg. It’s a bit like how the Venom symbiote attaches itself to Spider-man. (It seems unaffected by an attack of sounds waves, such as my daughter playing “Fight song” by Rachel Platten 17 times in a row. Thus I deduce it is not an actual symbiote. I have not tested the stocking's reaction to fire for tolerably obvious reasons.)
Once on, it is almost possible to forget that it is there, unless you develop an allergic reaction to the material, as I have done. In which case, you're caught between a rock and a hard place, at least until you get a different material or your doctor clears you to take a break from wearing them.
The stocking can be removed at night. Vendors advise putting them on first thing in the morning, when leg swelling should be low.
Vendors advise washing in their expensive custom solution, but mild soap is perfectly adequate.
Contrast diabetic socks, which are designed not to compress the foot and ankle.
* Yes, actually, and I feel 50% more metrosexual
due to the name alone.