Sclerotherapy is a minimally invasive procedure designed to eliminate unwanted veins, primarily spider veins and smaller varicose veins, often found in the legs. The treatment involves injecting a liquid or foam chemical solution, known as a sclerosant, directly into the affected vessel. This substance irritates the vein lining, causing it to collapse, seal shut, and eventually be absorbed by the body, rerouting blood flow to healthier veins. The total number of sessions required for complete resolution is highly individualized, depending on the severity and extent of the vein issues being treated.
Factors Determining the Number of Sessions
One primary consideration is the size and type of the vein. Spider veins, which are the smallest and most superficial, generally require fewer sessions compared to reticular veins, which are slightly larger and often feed the spider vein network.
Small varicose veins, being larger in diameter and deeper, typically demand a greater volume of sclerosant and more sessions to achieve full closure. The sheer extent of the area being treated is also a major factor; a widespread network of veins across both legs will naturally require more treatment time than a small, localized cluster. A patient’s overall circulatory health and medical history, including any prior vein treatments, can also affect how well the veins respond to the injection and how many sessions are needed for a lasting result.
The concentration and type of sclerosant solution used affects the procedure’s effectiveness and the maximum safe dosage per visit. Because of this safety limit, extensive vein networks must be treated across multiple appointments. The body’s natural response, including the rate at which the treated vein scars and is absorbed, also dictates the timeline for follow-up sessions.
Typical Treatment Schedules and Session Counts
The number of treatments needed is typically provided as a range, which varies significantly depending on the target vein. For isolated spider veins, patients often require between two and four sessions to achieve satisfactory clearance. Small varicose veins or more complex, widespread spider vein networks may necessitate a higher number of sessions, potentially ranging from four to eight or more for complete closure.
Sessions are not performed consecutively; a necessary waiting period is built into the schedule. Most practitioners space appointments four to six weeks apart to allow the body time to process the treated veins. This spacing is essential because the procedure is a gradual process of vascular healing, allowing the vein to scar down and begin the absorption process. Waiting permits the clinician to assess the full effect of the previous injection and prevents interference with the body’s safe absorption of non-functional vein tissue.
Post-Treatment Expectations and Maintenance
The initial course of treatment is considered complete when the targeted veins have faded significantly and the clinician confirms the vessels are closed. Successful resolution generally results in a 50% to 80% reduction in the appearance of the treated veins. Spider veins usually fade within three to six weeks, while larger vessels may take three to four months to fully disappear.
Treated veins that successfully close will not reappear, making the results of sclerotherapy permanent for those specific vessels. However, the procedure does not prevent the formation of new veins in the future, as it does not change the underlying predisposition for venous insufficiency. New spider or varicose veins may develop over time, requiring “touch-up” sessions every few years for maintenance.
Follow-up appointments are routinely scheduled a few months after the final injection to confirm the treated veins have fully closed and address any spots needing minor additional treatment. Maintaining results is supported by lifestyle factors, such as wearing compression stockings and engaging in regular physical activity. These practices promote healthy circulation and reduce the risk of new vein development.