A Shot of Youth: Neurotoxin

By Dr. Paul M. Graham

A Shot of Youth: NeurotoxinYou are probably aware of the use of botulinum toxin in the field of aesthetic and cosmetic medicine, but do you know how it was discovered and how it works? In this article, we will discuss the historical significance, mechanism of action, indications for, and side effects of this powerful, yet popular neurotoxin. The word neurotoxin sounds intimidating to many but is well-understood by few. With such a powerful substance, it is natural to be cautious when deciding to undergo treatment. I hope this article helps to increase the understanding of this industry-changing medication, in addition to answering your questions about its use.

History of Botulinum Toxin
In the 1960s, an ophthalmologist named Dr. Alan Scott experimented with injecting botulinum toxin to treat patients with crossed eyes (strabismus) and eyelid muscle spasms (blepharospasm. He saw significant improvement in both disorders. It was then discovered that botulinum toxin could also be used in other body locations for the treatment of muscle spasms. The toxin’s use soon gained popularity among physicians for the treatment of bladder spasms, writer’s cramp, cerebral palsy, and excessive sweating.

Botulinum toxin is a neurotoxin derived from a bacteria called Clostridium botulinum. This bacteria is often found in an inactive form in soil, lakes, and streams. The bacteria become pathogenic when bacterial counts increase to a point such that excess toxin is produced. The effects of this toxin were first discovered in 1820 after a food poisoning incident involving blood sausages killed several dozen German citizens.

During the early 1990s, one of the most important discoveries was made. Dr. Jean Carruthers, an ophthalmologist, found that her patients who underwent botulinum toxin injection for eyelid spasm often appeared younger, with softening of the frown lines in the central face. One of the first published papers evaluating the use of neurotoxin for the treatment of wrinkles was subsequently published by Drs. Jean and Alastair Carruthers.

In 2002, botulinum toxin officially received FDA approval for the treatment of wrinkles in the central face. Today, botulinum toxin is the #1 non-surgical cosmetic treatment in the United States with an estimated 6.7 million treatments performed in 2014, as reported by the American Society of Plastic Surgeons (ASPS).

How does it work?
Botulinum toxin is one of the most toxic substances known to man, but its dangerous effects only occur at toxin concentrations far exceeding the doses typically

used for cosmetic procedures. Over the years, cosmetic botulinum toxin dosing has changed significantly, going from higher dose imparting a “frozen” look, to lower doses resulting in a more subtle, “natural” look. Societal norms have slowly shifted towards more balanced facial rejuvenation, with less focus on complete facial paralysis.

Botulinum toxin works by blocking the signal from actively firing nerve cells to corresponding muscles, preventing further muscle contraction. In scientific terms, the neurochemical messenger known as acetylcholine acts as an important signaling molecule responsible for initiating and maintaining muscle contraction. Botox blocks the release of these molecules, preventing the formation of expression-induced wrinkles and softening pre-existing lines.

Botulinum toxin is sold commercially under several brand names including Botox® (OnabotulinumtoxinA), Xeomin® (IncobotulinumtoxinA), Dysport® (Abobotulinum-
toxinA), and Myobloc® (RimabotulinumtoxinB).

After an injection of botulinum toxin, you can expect to see clinical effects within the first 5 days, peaking at 2-3 weeks. The results can last up to 3-4 months. The length of time required until seeing clinical results represents the time it takes for the botulinum toxin to fully disrupt nerve conduction to the muscles being treated. Routine use of botulinum toxin (every 3-6 months) can increase the duration of improvement between subsequent treatment sessions. Subsequent treatments also often require lower doses of botulinum toxin.

This is because repeated treatments induce mild muscle atrophy (shrinking) and weakening. This phenomenon has been shown histologically (biopsy-proven) in at least one study.

Medical Uses
Botulinum toxin is most commonly used for the reduction of adult facial fine lines and wrinkles. However, the use of botulinum toxin is not limited to the field of cosmetic. Its utility continues to expand across various medical specialties. Currently, botulinum toxin is or has been used in the treatment of blepharospasm (eyelid spasm), chronic migraines, strabismus (crossed eyes), hyperhidrosis (excess sweating), overactive bladder, muscle spasticity, cervical dystonia, facial contouring, and teeth grinding.

Adverse effects
Despite its consistently proven safety profile, botulinum toxin does have the potential to cause some temporary side effects. These are often related to the injections themselves and include mild pain, local swelling, bleeding, minor headaches, and temporary upper eyelid drooping. Importantly, botulinum toxin is not recommended for use in women who are pregnant or lactating.

In summary, botulinum toxin injections have increased significantly over the past decade. Botulinum toxin remains the most popular cosmetic procedure overall for both men and women. It is most commonly used for the treatment of fine lines and wrinkles on the adult face but has many other medical indications. Injection of botulinum toxin by a board-certified dermatologist is a safe and effective anti-aging treatment that provides temporary muscle weakening, resulting in a more youthful and rested appearance. For more information or to find out if you are a candidate for botulinum toxin injections, contact Associates in Dermatology at (239) 936-5425.

References:
1. Nichols, H. “Botox: How Does Botox Work?.” Medical News Today. 2015; October 14
Retrieved from http://www.medicalnewstoday.com/articles/158647.php.
2. Therapeutic Biologic Applications, FDA Medical Officer’s Review, 4 March 2002,
Retrieved 25 July 2016.
3. Botulinum toxin A inhibits acetylcholine release from cultured neurons in vitro, Ray P,
PubMed, In Vitro Cell Dev Biol Anim. 1993 Jun;29A(6):456-60.
4. Choi WH, Song CW, Kim YB, et al. Skeletal muscle atrophy induced by intramuscular
repeated dose of botulinum toxin type A in rats. Drug Chem Toxicol. 2007;30(3):217-27.
5. http://www.nbcnews.com/id/21369061/ns/health-skin_and_beauty/t/frozen-time-
botox-over-years/#.V467UZMrIzW
6. http://www.plasticsurgery.org/Documents/news-resources/statistics/2015-statistics/
2015-plastic-surgery-statistics-report.pdf
7. Dressler D. Botulinum Toxin Therapy. Stuttgart: Georg Thieme Verlag; 2000

*Please note, our medical disclaimer applies to all information, images, recommendations, and comments published on this page.

Associates in Dermatology
239.936.5425
www.associatesinderm.com

8381 Riverwalk Park Blvd.
Fort Myers, FL 33919