Normally veins move blood up the leg against gravity using a series of valves that stop blood from going the wrong way. Venous reflux occurs when those valves stop working properly, leading to congestion in the leg.
Compression stockings work by forcing the blood up the leg in people who have venous reflux, yet can be difficult to wear because they are very tight and can lead to discomfort, especially during the warmer months.
Prescription based stockings are tighter than over-the-counter stockings and can come with varying degrees of compression and length.
In addition to being part of initial treatment, compression stockings are used briefly following any type of vein procedure. Often, insurance carriers will want to see that you have worn compression stockings without relief or with significant discomfort before they will approve any type of definitive procedure to correct varicose veins.