A professional hair removal laser machine doesn't purposely heat up the skin, most machines for hair removal are using a wavelength with a short burst cycle that will heat up the melanin in the hair and use the hair shaft to transfer the heat to damage the hair bulb.
A professional hair removal machine with correct settings shouldn't have any effect on varicose veins. The laser use for varicose veins treatment is more focus and powerful.
The side effect of laser removal:
- Dry skin
- Pigment changes
- Increase hair grow
http://www.mayoclinic.org/tests-procedures/laser-hair-removal/basics/risks/prc-20019438
