Foam sclerotherapy is the latest development in the sclerotherapy field and is a more effective way to deliver the sclerosing agent directly to the problem vein. Foam sclerotherapy is a technique that involves injecting foamed sclerosant chemical within a blood vessel using a very small syringe. The “foam” works by forming a bond between the red blood cell and the foaming agent. This, in turn, creates a goo-like substance inside the vein which sticks to the wall of the vessel causing the vein to close. The procedure takes about 15 minutes, and typically the veins are reduced in 3 to 4 weeks.