Roma, Italy: Nancy Galan, MD. BOTOX is primarily used to smooth lines on the upper part of the face, particularly frown lines, forehead lines, and crow's feet. These lines can add years to your appearance and project a false impression of depression, anger, or concern. BOTOX can also be used to improve fine and deeper lines in the upper lip, the "downward smile" in the corners of the mouth, to mitigate excessive gum show on smiling, and smooth the creases and folds in the neck.