Time for some science. Ultrasound gel is meant as a coupling agent between the skin and transducer. It helps the ultrasound energy enter the body, scatter off all the organs and tissues in the way, and come back to the transducer to create a beautiful image. Without ultrasound gel, most of the ultrasound energy will get scattered on the surface of the skin and there won't be enough inside the body to create a good image. That's it's true purpose.
Light (and lasers) is completely different. If a gel is used it has a different function. It is meant to cool the surface of the skin and prevent burning but doesn't change the way the laser energy propagates (unless it's too thick then the light will scatter away, barely enter the skin and essentially have no effect on the hair root- which makes it useless). Light scatters a LOT more than ultrasound which is why it can penetrate just deep enough to hit the hair roots but you don't have to worry about it affecting any organs more than about half a centimeter deep. Since you're only targeting the hair root, there is no benefit to burning the surface of your skin, the gel can cool it while allowing the roots to burn.
I've been using aloe vera gel sometimes with and sometimes after the laser since it's cheap and soothing and I haven't gotten any burn marks.
answered 1 year, 8 months ago
I got mine from another vendor at a special price that included the calming gel. The gel merely comforts & cools the skin during treatment due to the warmth/heat that the laser emits. It is Not Necessary, but you may want it if skin is sensitive. I only use gel on sensitive areas of body
answered 2 years, 10 months ago