Vein Sclerotherapy is a common treatment for varicose veins and smaller visible veins called reticular veins or telangiectasia (spider veins or thread veins). Sclerotherapy or injection of varicose veins is an ambulatory procedure (walk-in walk-out) carried out as an outpatient. Using a very small needle the surgeon injects the veins with a liquid or a foam (solution mixed with air) solution called a sclerosant which damages the internal lining of the vein and causes blood clot to form within the veins. In time your own body will then destroy the vein and it will gradually disappear. The solution normally used for this is available in different concentrations depending on the size of the vein being treated. Usually a temporary bandage or compression stocking is applied to the leg after treatment. The treatment will normally take only 20 minutes and either one or both leg and you will be able to walk out of the outpatients afterwards. Most patients experience only very mild discomfort and return to full activity and work (if relevant) usually the same day.