I Had Sclerotherapy Done Yesterday on Right Leg Behind Knee. My Leg is Swollen to my Toes?

After undergoing sclerotherapy treatment for leg veins, it's very common for patients to experience leg swelling, especially if they do not continue to wear their compression garment as advised. Typically, compression garments should be worn around the clock for the first several days. I do not recommend compression dressings but graduated compression stockings. If a compression dressing is not properly applied with the correct bandage, the compression can make things worse.
Though it is rare, swelling may be a sign of a blood clot, and if it continues, you may want to visit your doctor or seek a second opinion. As a cosmetic laser dermatologist in San Diego and a pioneer of sclerotherapy treatment, I would advise you to contact your doctor to make sure you are healing correctly.

I would highly recommend that you seek medical attention and follow-up with your treating physician. 

Swelling after sclerotherapy can be a sign of a blood clot, and one should seek immediate medical attention. Please contact whoever performed the surgery for you to ensure that you are healing correctly.