One of the two most common medical indications is essential benign blepharospasm, a condition in which there is involuntary twitching of the eyes. Patients with this condition also have a certain inability to open their eyes. In these cases, botulinum toxin is applies in order to allow patients to open their eyes and do their tasks normally. Another medical indication is hemifacial spasm, which produces something similar to a tic in which the patient presents involuntary twitching on one half of the face. If botulinum toxin is used correctly, it can minimize this problem. The cosmetic or esthetic uses of botulinum toxin are concentrated in the upper half of the face.

In this part of the face there are three areas where it is typically possible to use the toxin safely. One is the so-called “crow’s feet”, wrinkles that appear on the sides of the eyes due to the action of the muscles that close the eye and that typically become visible when smiling. Proper application in that area can reduce muscle contraction and minimize the amount of wrinkles. It can also be used in the forehead and in the area between the eyebrows. In addition to reducing wrinkles, the proper use of botulinum toxin can give eyebrows a different shape and height to achieve a better esthetic result. In the lower half of the face, it can be used to smooth the smile lines that occur at the sides of the mouth and to smooth some wrinkles of the lips, but, as mentioned before, its most common use is in the upper part of the face.