Author: Min Ahn
In 1987, Dr. Jean Carruthers, a Vancouver oculoplastic surgeon, discovered that she could inject botulinum toxin A into muscles around the eye and temporarily smooth out wrinkles. Four years later, she and her husband Dr. Alastair Carruthers, a dermatologist, published their findings. This report launched what would become the most commonly performed aesthetic treatment.
Some patients ask if Botox® is dangerous. The simple answer is that Botox® is a medication that is a purified protein derived from the botulinum toxin. In the form that is FDA approved and produced by the manufacturer, it is highly regulated and controlled. In essence, it is a medication and like others, Botox® has a therapeutic dose and a toxic dose. The amounts used for treating wrinkles of the upper face do not come close to the levels that would cause toxicity.
As an illustration consider Tylenol® (acetaminophen). When taken as directed, the over the counter pain medication is highly effective for headaches. If one were to ingest a whole bottle of Tylenol®, it would have severely damaging effects on the liver and could possibly result in death. All medications share this feature of having a therapeutic range that is limited by a dose that is safe and a dose that is toxic. Botox is no different and when used properly is highly safe and effective for treating certain facial wrinkles.
Botox® in its cosmetic version and non-cosmetic form (both chemically identical) are FDA approved for:
Temporary improvement in the appearance of moderate to severe glabellar (frown) lines
Cervical dystonia (muscle spasm of the neck)
Severe primary axillary hyperhidrosis (excessive sweating)
Strabismus (“lazy eye”)
Blepharospasm (spontaneous spasm of muscles surrounding the eyes)
The most common problems for which Botox® is used are cosmetic in nature and are what some refer to as “lines of facial expression”. These include the frown and forehead lines and crow’s feet. The frown lines happen to be the lines that were specifically tested for FDA approval. As with many medications, the list of FDA approved indications only reflects the specific areas that were tested during the approval trial. After a medication has been FDA approved, a doctor can use it in an “off label” manner. Therefore using Botox® to smooth forehead lines and crow’s feet, to lift the eyebrows and to smooth lip lines are considered off label treatments. Lifting the outer eyebrow, “the Botox Browlift”, was originally described by this author in 2000. In this study, it was determined that placing Botox® in the crow’s feet area and just under the tail of the brow would weaken the muscle that pulls down on the brow and allow the muscle that lifts the brow to take effect. This would indirectly lift the temporal brow non surgically.
Botox® comes in a vial containing 100 units of a dry powder. It is then reconstituted with injectable saline. Typically the final concentration is 2.5units/0.1cc. The liquid solution of Botox® is then injected into muscles that are targeted for relaxation. These are the same muscles that contract with facial expression and cause creases to form. Once injected, Botox® will bind to specific receptors at the ends of motor nerves (nerves that move the muscle) and prevent the release of a neurotransmitter (acetylcholine) that normally causes the muscle to move. As a result, the muscle is effectively relaxed. Since the muscle is no longer contracting and forming creases many times a day, the skin then smoothes itself out. Therefore the smoothing effect on the wrinkle is indirect since Botox® does not directly fill the line. This effect typically lasts 3-4 months because the nerves sprout new connections with the muscles that override the Botox® effect. Botox® has no effect on nerves that provide sensation.
The treatment is performed by a qualified and well trained practitioner who may be a doctor, nurse, nurse practitioner or physician’s assistant (depending on the state rules). Botox® is injected with a small needle (30-32 gauge) without any need for anesthetic. Some people may request ice or a numbing cream. The treatment feels like a small pinch and takes about 10 minutes. Immediately after, the area will look no different in terms of the wrinkle as the Botox® effect takes several days to start working. This is truly an in and out (“lunchtime”) procedure. Within a few days the patient will notice that the treated area does not move with effort and the wrinkle has improved. Often the wrinkle is no longer visible.
The most common side effects are minimal bruising at the injection site or a mild headache. The bruising is minor and temporary and can be covered with makeup. Any headache is also temporary and can be treated with acetaminophen. Other reported side effects include dry mouth, discomfort or pain at the injection site, tiredness, neck pain, and eye problems: double vision, blurred vision, decreased eyesight, drooping eyelids, swelling of the eyelids, and dry eyes.
In terms of the potential for a drooping (ptosis) eyelid, this is caused by Botox® inadvertently affecting the muscle that lifts the eyelid, the levator muscle. This is very uncommon and if it occurs it is temporary (lasting less than a few weeks) and more importantly treatable. Eye drops that directly stimulate the levator muscle (Iopidine) will correct the ptosis until the function returns.
When excessive amounts of Botox® are used severe side effects can occur including problems with swallowing, speaking, or breathing, and allergic reactions. No occurrences of such severe side effects have been reported with standard amounts of Botox Cosmetic®. Patients with neurologic disorders such as amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease), myasthenia gravis, or Lambert-Eaton syndrome should not have Botox® treatments. It is not known if BOTOX® Cosmetic can be used safely in pregnant or breast-feeding women and therefore most practitioners will not do so.
Temporal brow lift using botulinum toxin A. Ahn MS, Catten M, Maas CS. Plast Reconstr Surg. 2000 Mar;105(3):1129-35
A multicenter, double-blind, randomized, placebo-controlled study of the efficacy and safety of botulinum toxin type A in the treatment of glabellar lines. Carruthers JA, Lowe NJ, Menter MA, Gibson J, Nordquist M, Mordaunt J, Walker P, Eadie N; BOTOX Glabellar Lines I Study Group. J Am Acad Dermatol. 2002 Jun;46(6):840-9