You should avoid certain medications. Talk to your doctor about all medicines (including over-the-counter drugs, herbs, and dietary supplements) you are taking before the procedure. Some doctors recommend avoiding aspirin, ibuprofen (for example, Advil, Motrin and Nuprin), or other anti-inflammatory drugs for 48-72 hours before sclerotherapy.
If you need to take an antibiotic, tell your doctor.
It's best to wear shorts to the procedure, but don't put lotion on your legs.