Your varicose veins have been injected with a special medication during a treatment called sclerotherapy. This medication causes a blockage in your varicose veins. This forces the blood to go around the blockage and travel through nearby healthier veins, increasing blood flow in your legs. This pamphlet gives specific directions to prevent blood clots from forming in your healthy veins. Mild side effects and a list of symptoms that require immediate medical attention are provided.