The glabella is the area between the eyebrows, above the root of the nose. Contraction of certain muscles can produce vertical or horizontal lines here. These are often called frown lines, but the appearance of this area does not reveal a person's mood.
Botulinum toxin can temporarily reduce the activity of selected muscles used in facial expression. Lines already visible at rest cannot always be completely smoothed in this way. Their severity, facial movement and eyebrow position are assessed before treatment.
Possible side effects include bruising, headaches, asymmetry and temporary drooping of an eyelid or eyebrow. Filler injections in this area require particular caution because of the arrangement of its blood vessels.