Radiofrequency treatment is based on electrically heating the skin and can be anything from extremely safe all the way to very unsafe (and with a lot of adverse reactions), depending on type of radiofrequency used, equipment and therapist experience/training. If the pain threshold rule is adhered, deep-acting, high-power radiofrequency provided in a continuous moving fashion, should be ~99.5% safe, or better…
Radiofrequency, collagen stimulation and skin tightening
The main thing that radiofrequency does is to tighten skin. This happens via two mechanisms: RF stimulates existing collagen contraction; RF stimulates new collagen and elastin synthesis. In fact radiofrequency is the best way to achieve both collagen contraction and production. Any other technique is simply not effective enough, unsafe or both.
When it comes to skin tightening / toning / lifting, radiofrequency is the only game in town.