Neurotoxin Myths: What does the research say?

Neurotoxin Example Photo

We performed a review of the scientific literature about neurotoxins to determine what was truth and what was myth.

What are the myths regarding neurotoxin treatments? 

  1. Different neurotoxins yield different results: There is no compelling evidence that one neurotoxin is more effective than the others. There are several low quality studies reported in the literature that demonstrate mixed results with numerous limitations. Any differences reported are more likely related to doses used and there is no formally accepted conversion rate between the products. 
  2. Diffusion profiles differ between the neurotoxins: spread of neurotoxin after injection refers to the relatively rapid physical movement of toxin from the original injection site, which is influenced by the injection technique including the volume injected, speed of injection, and angle of injection. Diffusion, however, refers to the relatively slow kinetic dispersion of toxin beyond the original injection site, which characterizes the toxin’s movement to receptors. Studies have shown that dose, not the type of neurotoxin, is the main driver of diffusion with higher doses diffusing into a larger area.  
  3. Protein load is clinically important: Some have suggested that complexing proteins with the botulinum toxin can limit the spread and diffusion of toxin from the target tissues. However, there is no clinical evidence that this is true. Moreover, it has been shown that neurotoxins with complexing proteins (Botox and Dysport) dissociate the complexing proteins when mixed in the vial, not injected into the skin. 
  4. Formation of antibodies are an important determinant of treatment failure in facial injections: The development of antibodies is comparable across the three different neurotoxins, ranging from 0-3%. Studies have shown that formation of antibodies is related to higher doses rather than type of neurotoxin. A study evaluating patients who were secondary nonresponders to neurotoxin treatments found antibodies in less than 50%, indicating that there are other factors contributing to non responsiveness over subsequent treatments. 
  5. Reconstitution solution matters: Studies have shown that reconstitution with preserved saline dramatically improves patient comfort without compromising efficacy (compared to preservative-free saline), whereas aggressive reconstitution may reduce efficacy. 
  6. Volume of injection matters: Different injectors use different dilutions that contain the same overall amount of neurotoxin, just with varying volumes of saline used for reconstitution. For example, one injector will dilute 6 units of Dysport into 0.1mL of saline, whereas another injector will dilute 6 units of Dysport into 0.3mL saline. Studies currently show that the amount of neurotoxin matters (6 units of Dysport), not the amount of saline used to reconstitute it (0.1 vs 0.3mL). 


Neurotoxin injections are the leading nonsurgical cosmetic procedure worldwide with a high rate of efficacy and patient satisfaction. These injectable medications can be used to treat a variety of conditions, most commonly dynamic wrinkles of the face. There are several formulations of neurotoxin available without significant differences between the different types. At Studio R Aesthetics, all toxin injections are personally performed by Dr. Segura because she believes that the results achieved with toxins are greatly dependent upon the training, experience and skill of the person performing the injection. 

About Dr. Brandy Segura

Committed to continuing medical education and providing world-class treatment and care to the Charlottesville community, Dr. Segura has traveled across the U.S. to get hands-on training with the experts in aesthetics. With her unique background in nutrition optimization, hormones, and bodybuilding, Dr. Segura has written multiple articles for,, and sports nutrition companies. She has been featured on as well as Muscle & Fitness Hers magazine and was dubbed “Transformation of the year” by in 2013. Now she is using her training, experience and artistic talents in helping patients look and feel their best.

About Studio R Aesthetics

Studio R Aesthetics is a physician-owned, physician-run Medspa and Physician Practice in Charlottesville whose priority is to ensure that patients receive the best aesthetic results and outcomes that exceed their expectations. We opened this practice because as both physicians and patients, we have a unique perspective on how to deliver the highest quality patient care. We treat every patient as if they were a family member.

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