Botulinum toxin injections are becoming increasingly popular and have been shown to safely decrease the appearance of fine lines and wrinkles on the face since its FDA approval nearly 15 years ago. The most common areas treated by dermatologists with botulinum toxin include horizontal forehead lines, frown lines (glabella complex) between the eyebrows, bunny lines on the side of the nose, and crow’s feet around the eyes. Due to the high safety profile and effectiveness of botulinum toxin, many other areas on the face have become targets for botulinum toxin therapy as discussed below.
Eyebrow lift and shaping:
Botox can be injected above and below the eyebrow in order to revert the scowling expression that can develop with aging. By dividing the toxin into different small doses at spaced intervals, one can shape and elevate the eyebrow to obtain a more youthful look.
Decrease bulging lower eyelids:
Bulging lower eyelids can occur as a result of hypertrophy of the orbicularis oculi muscle due to repeated contractions when smiling. This can be corrected with botulinum toxin injections which will relax the muscle and decrease the bulging and contraction over time.
Dense vertical lines around the lips, known as “smokers lines”, occur not only in smokers but also secondary to genetic factors, sun damage, repeated pursing of the lips from playing musical instruments, etc. Botulinum toxin treatment of the orbicularis oris (the muscle responsible for the purse-string-like movement of the lips) is recommended to treat the deep lines. Very small aliquots around the lips will decrease the appearance of the deep lines and result in more youthful lips.
During a smile, the upper lips in some individuals may retract too far and result in an excessive exposure of the upper gums. The levator labii superioris alaeque nasi muscle is the culprit and its overactivity can be controlled with botulinum toxin injections.
Marionette lines are folds that extend from the angles of the mouth down to the chin and are exacerbated by the depressor anguli oris muscle. Soft tissue fillers are the best option to treat these lines, but botulinum toxin can be used as an adjunctive therapy to help decrease the downward pull on the corners of the mouth and provide longer lasting results in these lines.
A frowning expression occurs as a result from the corners of the mouth becoming permanently angled downward. This can bother some patients as it gives an impression of unpleasantness or disapproval. The depressor anguli oris muscle is overactive in this case, and it can be the target of a botulinum toxin treatment to allow the angles of the mouth to return to a horizontal position.
Contraction of the mentalis muscle can result in a very deep crease between the lower lip and the prominence of the chin. Fillers in this area may not always be the best option as they can result in visible beads of product underneath the skin. Botulinum toxin injections targeting the mentalis can soften this crease giving a more youthful appearance.
Bunny lines are wrinkles that occur on the nose when we smile. The muscle responsible for the formation of these lines is called the nasalis. This sheet-like muscle lies directly over top of the nasal bridge and is usually accentuated during smiling. During muscle contraction, vertical lines are formed on the upper part of the nasal sidewall. Botulinum injections target the nasalis muscle to decrease the strength of muscle contraction, therefore decreasing the vertical bunny lines. Filler is not a great option for treatment of these lines as they are primarily muscle-driven rather than static lines on the skin.
Horizontal neck lines:
Horizontal neck lines are lines of indentation seen in the neck of many patients, and those can be softened with botulinum toxin treatments. They occur at the sites of attachment of the superficial musculoaponeurotic system (SMAS) of the face. Multiple small doses of botulinum toxin are injected very superficially along the horizontal lines which will soften over time.
Platysmal bands are strips of muscles that extend from the underside of the jaw to the base of the neck. The platysma muscle is responsible for the formation of vertical protruding neck bands that are accentuated during lower lip retraction and grimacing. The platysma is a sheet-like muscle the covers the anterior neck and is attached directly to the skin. Botulinum toxin can be used in numerous small aliquots along the length of the muscle to soften and relax each band.
Hypertrophy of the masseter muscle and bruxism:
The masseter muscle is a muscle of mastication (chewing) and it sits at the angle of the jaw. It can be enlarged in some patients leading to a more squared-off face and may also be the cause of bruxism (grinding teeth). Both of those conditions can be treated with high doses of botulinum toxin injected directly into the masseter muscle. By correcting the squared-off lower face, this gives a more youthful and feminine heart shaped face.
Botulinum toxin can also be used to treat facial asymmetry as a result of facial nerve palsy, surgery, trauma or dystonia (muscle spasm). It can be applied to decrease muscle movement on the unaffected side in case of nerve damage, or it can be injected on the overactive side in the case of dystonia.
Hyperhidrosis (Excessive sweating):
Botulinum toxin blocks the release of acetylcholine by nerve cells. Acetylcholine is a neurotransmitter that stimulates the sweat glands to increase secretion. By injecting botulinum toxin into areas where excessive sweating occurs, we are able to reduce sweat production and effectively treat conditions such as hyperhidrosis. Botulinum toxin is aliquoted into 10-20 injection sites and injected into the axillae, palms of the hands, or soles of the feet. This is a successful treatment to decrease sweating and it is effective for approximately 6 to 12 months.
Dermatologists receive extensive training in facial anatomy and spend a large amount of time doing botulinum toxin injections. If you are interested in any of the options discussed above, schedule an appointment to see your dermatologist for a thorough evaluation to determine the best treatment that is right for you.
Additionally, make sure to check out Part 1 of this botulinum toxin series called Neurotoxin: A Shot of Youth for more information on how it works to soften lines and give a more youthful appearance.
- Dermatology. Third edition. 2012;159:2561-71.
- Mariwalla D., Leffell D. Dermatology surgery: a study companion. Second edition. 2011;17:103-8.
- Lowe N. Botulinum toxin type A for facial rejuvenation. Dermatol Surg. 1998;24:1216-18.
- Sutton A., McBurney E. Anatomy of the aging face. Dermatology surgery fundamentals. ASDS video review series.
- Sutton A., McBurney E. Complications from neurotransmitters. Dermatology surgery fundamentals. ASDS video view series.