Botox treatments use botulin toxin in a purified, safe form, injected into the muscle to cause the neuromuscular junction—the area in the muscle where the nerve joins it—to become disabled. This causes the muscle to weaken so that one no longer wrinkles the face.
These treatments are best used to clear up scowl lines between the eyebrows. If we inject Botox in that area one can no longer scowl. Residual lines can be filled with filler to flatten them even further.
Botox can also be used for crow's feet with good results. There are other areas of the face where Botox has been used, but it can make the face look rather immobile and not as natural.
I prefer a natural look, so I limit Botox to the forehead and crow's feet area.