The Ultimate Guide to Neurotoxins

Everything there is to know about neurotoxins—what they are, how neurotoxins work, and how the non-invasive injectable Botox came to exist.

What Are Neurotoxins?

Neurotoxins are injectable cosmetic treatments that contain botulinum toxin A, a protein that prevents muscles from contracting. This helps to reduce the appearance of wrinkles and lines caused by facial expressions like frowning and squinting.¹

History and development of neurotoxin injections

The development of Botox began in the 1970s as Dr. Alan Scott, an ophthalmologist, was looking for a way to help his patients with eye disorders so they wouldn’t have to go through extensive surgeries. Specifically, he was aiming to treat people with strabismus,  a condition that causes the eyes to be misaligned (or cross-eyed). In the 1970s, the outcome of strabismus surgery was far from perfect—as many as 40% of patients needed reoperation. Dr. Scott began investigating different substances that could be injected into muscles to weaken them and create permanent alignment changes and, in doing so, discovered the restricted local effect of injected botulinum toxin type A. The injectable would be tested and developed over the next 15 years and, in 1991, sold to the company Allergan, where the name was officially changed to Botox. Today, it’s used as a treatment to help with migraines, hair loss, drooling, and smoothing down wrinkles for cosmetic purposes.²

How Do Neurotoxins Work?

Neurotoxin treatments temporarily block local nerve signals, specifically the release of a neurotransmitter called acetylcholine, which is responsible for signaling muscles to contract. By preventing the release of acetylcholine, neurotoxins can relax the muscles and reduce the appearance of wrinkles and fine lines.

The Different Types of Neurotoxins

While they are commonly called Botox, there are actually four different FDA-approved neurotoxins: Botox, Dysport, Jeuveau, and Xeomin. While the active ingredient in each product is botulinum toxin type A, the biggest differences are in the concentration of neurotoxin in each medication, and any additional protein blends that may affect the diffusion and efficacy of the injection. The four injectables are also made by different manufacturers, which leads to different costs, potencies, and formulations. 

Botox

Botox® received FDA approval in April 2002 as a temporary cosmetic solution for frown lines between the eyebrows, later extending its approval to include forehead lines and crow’s feet, alongside various off-label applications. Manufactured by Allergan, Botox® commands approximately 80 percent of the botulinum toxin type A injection market. Its formulation includes protective proteins, which may lead to antibody development in some patients, potentially diminishing treatment efficacy over time. Inactive components consist of human albumin and sodium chloride, while a therapeutic variant addresses medical issues such as migraines and excessive sweating. Aesthetic treatments typically cost around $6 per unit for physicians, with the total number of units varying based on the treatment area. Results manifest within three to five days, peaking at two weeks, and generally last three to four months, influenced by individual metabolism and treatment location.

Dysport®

Dysport® gained FDA approval in April 2009 for the treatment of frown lines and, similar to Botox®, is also utilized therapeutically to alleviate muscle spasticity. Developed by Medicis Pharmaceutical, Dysport® is considered slightly less potent than Botox® due to differences in molecular weight. Although both products contain the same 150 kDa of BoNT-A, the protective proteins in Dysport® are not as uniform as those in Botox®, resulting in a greater diffusion rate that makes Dysport® suitable for larger treatment areas, such as the forehead, albeit potentially requiring more product for desired effects. The pricing of Dysport® is generally on par with Botox®, and it is formulated with human albumin, along with lactose and cow’s milk protein, rendering it inappropriate for individuals with milk allergies.

Dysport® may exhibit effects more rapidly, often within 24 hours, compared to Botox®, but some research indicates that its effects may not endure as long. This shorter duration could appeal to patients who are uncertain about their preferences regarding BoNT-A injections.

Jeuveau®

In February 2019, the FDA approved a new product intended solely for cosmetic applications called Jeuveau®. Its manufacturer, Evolus, aimed for Jeuveau® to compete effectively with Botox®, given that both share a molecular weight of 900 kDa, are composed of human albumin and sodium chloride, and yield comparable outcomes. However, Jeuveau® is priced 20 to 30 percent lower than Botox® and is marketed primarily towards millennials, indicating a strategy to establish a distinct market segment.

Although clinical data remains limited due to the product’s recent introduction, trials indicate that Jeuveau® exhibits a safety and efficacy profile similar to that of Botox®. Patients typically notice results within three to five days, with effects lasting between three to six months.

Xeomin®

Xeomin® received FDA approval for the treatment of frown lines in July 2011, and it is also authorized for addressing muscle spasticity and excessive drooling. Manufactured by Merz, Xeomin® is distinctive as it does not contain complex proteins with BoNT-A, although it includes inactive components such as human albumin and sucrose. This characteristic allows Xeomin® to be stored at room temperature, potentially making the injection process more comfortable for patients. The cost of Xeomin® is generally comparable to that of Botox® and Dysport®, but it may require fewer units to achieve similar results, particularly for patients who have developed resistance to other treatments due to its purified formulation.

The effects of Xeomin® injections typically become apparent within five to seven days and have a duration similar to that of Botox®, Dysport®, and Jeuveau®. 

Pre-Treatment Care

What to do before getting Neurotoxins:

• Avoid blood thinners and alcohol. It’s best to refrain from using blood thinners, such as Aspirin, Advil, and specific supplements like fish oil, as well as to avoid consuming a second glass of wine during dinner at least 24 hours before your injection. This precaution may reduce the likelihood of bruising, according to Dr. David Shafer, a board-certified plastic surgeon.³
• Show up the day of with clean, makeup-free skin. While it’s not an absolute must, arriving to your appointment with clean skin is preferable as it’ll save time at your appointment, says Dr. Shafer. 

What to do after getting neurotoxins:

• Keep your skin clean and your hands off your face. As a best practice, you’ll want to keep your skin nice and clean and avoid makeup for 12 to 24 hours post-injection, says Dr. Shafer. Additionally, it is crucial to avoid touching or manipulating the injected area to minimize the risk of infection, bruising, or the dispersion of the neurotoxin.
• Ice as needed. Cold therapy is beneficial for alleviating redness, bruising, and swelling at injection sites. Apply an ice pack or cold compress to the affected area for a few minutes following your treatment and as necessary throughout the day.
• Avoid lying face down for a few hours. Standing or sitting upright for a few hours post-injection will help the toxin from spreading or causing bruising. My advice is not to go directly from your injection to a massage where you are lying face down…but the next day, this is perfectly fine, says Dr. Shafer.
• Skip the strenuous exercise. A light workout or brisk walk is totally okay, but most experts recommend avoiding intense exercise for 24 hours post-injection.
• Hold off on other facials and cosmetic treatments. Wait two to three weeks after receiving Xeomin, Botox, or Dysport before undergoing microneedling, microcurrent, radiofrequency, or laser treatments.
• Book a follow-up. In general, it takes five to seven days for neurotoxins to set in and for you to notice a smoothing effect—so don’t panic if you’re not seeing results immediately. That said, you may need to make a second appointment with your provider for a little tweak, says Dr. Shafer, who recommends waiting one to two weeks before doing so.

¹National Library of Medicine. Early development history of Botox (onabotulinumtoxinA). July 2023. Source

²Deepa Shivaram. Alan Scott, the doctor credited with developing Botox for medicine, dies at 89. NPR. Dec 2021. Source

³Lauren Balsamo. Your Ultimate Pre- and Post-Care Guide to Neurotoxins. Cosmopolitan. June 2023. Source