how long does it take for spider veins to disappear after sclerotherapy
2 years ago by Vein Treatment and Aesthetic Center It usually requires a few sclerotherapy treatments (spaced 3 weeks apart) for the veins to completely disappear. In my experience, it typically takes an average of 3 treatments for each spider vein.4 years ago by Laser Vein Center The short answer is most disappear in 6 to 8 weeks but some may take as long as 8 months.fter sclerotherapy spider veins may take 4 to 6 weeks to resolve. However, sclerotherapy often requires multiple treatments and I usually tell patients that some veins will disappear within several days, some within several weeks and some will need several treatments.