Sclerotherapy procedures have evolved in recent years. The types of sclerosing agents and advances in ultrasound imaging have improved to produce optimal results. Sclerotherapy is recommended for the treatment of small to medium sized varicose veins and telangiectasias, or spider veins.

Spider veins are smaller than varicose veins and not often painful, though many may be ugly. They are perpetually dilated veins that can range from dark blue to red in color. Spider veins can be caused by inefficient blood flow and a weakening of the vein's wall due to obesity, pregnancy, or numerous other factors.

Sclerotherapy is considered a minimally-invasive procedure typically performed in the office, by a qualified specialist. They evaluate a patient's needs and provide recommendations regarding the most effective course of action in the treatment of the patient's varicose or spider veins. The number of treatment sessions and injections per treatment will depend on factors such as the size, depth, and location of the veins requiring treatment.

For treatment the skin is cleansed, and veins are injected with a sclerosing agent. Treatment begins with the larger veins, then smaller ones, stretching the skin over the veins for even dispersal. One injection is commonly required for every inch of vein. A slight stinging or burning sensation is normal during and immediately after the procedure and will dissipate quickly. Due to the small diameter of the injection needle, patients are typically comfortable throughout the procedure. No anesthetic is needed. The injection process ordinarily takes 15 to 30 minutes to perform.

After injections, compression stockings are worn for three weeks to support the resolution of treated veins and enhance the circulation through healthy veins. Normal activities may be resumed immediately, though strenuous exercise should be avoided for a few days. It takes some time to see the full results of the treatment. There is usually some bruising and discoloration. There may be lumps or bumps at the injection sites. These reactions fade away and are gone within a few weeks. Additional treatments, if needed, can be scheduled every four to six weeks until all areas are treated.