Selecting the Right Neuromodulator

Neuromodulator injections remain among the most commonly performed aesthetic treatments worldwide, yet the growing number of available products has raised an increasingly common question from patients and clinicians alike: are all neuromodulators the same? The answer is both yes and no. While the US Food and Drug Administration (FDA)-approved options currently share important similarities, subtle differences in formulation, diffusion, and clinical effect can influence how and when each is used.

A SHARED FOUNDATION
All neuromodulators currently approved for aesthetic use in the United States are based on botulinum toxin type A. Because they share the same fundamental mechanism of action, blocking acetylcholine release at the neuromuscular junction, their clinical effects are broadly similar when used by experienced injectors.

For this reason, differences that patients attribute to the products themselves often actually reflect factors like injection technique, which includes dilution and injector preference/skill. Neuromodulators are supplied as powders that must be reconstituted with saline before use, and variations in dilution can influence spread and clinical outcomes. More important is the placement of product by the injector. In the minority of cases, there are patients who do respond better to one brand over another. 

Despite these similarities, each product is processed slightly differently by the manufacturers, resulting in some meaningful distinctions.

FORMULATION AND ACCESSORY PROTEINS
One of the key differences among neuromodulators is the presence (or absence) of accessory proteins. Most formulations, such as onabotulinumtoxinA (Botox, Allergan Aesthetics) include proteins attached to the botulinum toxin during processing. These proteins generally do not change the clinical effect of the toxin but may influence how the immune system recognizes the product. One option, daxibotulinumtoxinA-lanm (Daxxify, Revance), has an accessory peptide that is positively charged to bind the neurotoxin to the negatively charged neuronal membrane for a potentially longer duration of effect. However, a longer duration has not been consistent in my clinical experience.

IncobotulinumtoxinA (Xeomin, Merz Therapeutics), meanwhile, contains only the purified botulinum toxin molecule without accessory proteins. This may reduce the risk of immune recognition and potential loss of efficacy over time. An analysis on neutralizing antibodies from 14 aggregated randomized controlled trials involving the five main botulinum toxin A products showed that Xeomin is associated with the lowest likelihood of immunogenicity.¹

DIFFUSION AND PRECISION
Another factor that can influence product selection is diffusion, or how widely the toxin spreads after injection. AbobotulinumtoxinA (Dysport, Ipsen Biopharmaceuticals Inc.), for example, is often perceived to diffuse more broadly, which can be advantageous in younger patients who prefer a softer, more blended effect. Conversely, some clinicians view products such as prabotulinumtoxinA-xvfs (Jeuveau, Evolus) as providing more localized activity, which may be helpful in patients who require precise treatment or who are at higher risk for unwanted muscle relaxation in nearby areas.

ADJUSTING FOR PATIENT PREFERENCE
Neuromodulator selection is often guided less by strict rules and more by patient-specific goals. Some individuals prefer a strong, immobile result, while others want subtle softening that preserves facial movement.

Formulations such as Xeomin can provide a softer effect that maintains natural expression, which may be appealing for first-time patients, actors, or individuals in the public eye who want their treatments to remain undetectable. Conversely, patients who prefer a more pronounced reduction in movement may benefit from other formulations.

Treatment can also evolve over time. Patients who initially choose a softer effect may later request a stronger result, prompting a switch in neuromodulator type. The reverse is also common when patients feel their treatment feels too tight or heavy.

Switching neuromodulators is occasionally necessary when patients report shorter duration of effect after many years of treatment. Although uncommon, neutralizing antibodies may occur, potentially reducing effectiveness. In these situations, changing to a different formulation—particularly one without accessory proteins—may restore response.

BOTTOM LINE
Despite direct-to-consumer marketing, the category continues to be referred to as Botox by unfamiliar patients. In clinical practice, many patients rely primarily on the injector’s expertise rather than requesting specific products.

Ultimately, neuromodulator selection involves balancing several practical considerations: formulation, diffusion characteristics, patient preference, and prior treatment history. While subtle differences exist among products, experienced clinicians can achieve excellent outcomes with any of the currently available options. Rather than focusing solely on brand names, the most important factor remains thoughtful, individualized treatment planning. When neuromodulators are selected and administered appropriately, they remain one of the safest and most effective tools in aesthetic medicine.

1. Rahman E, et al. Intradermal Botulinum Toxin A on Skin Quality and Facial Rejuvenation: A Systematic Review and Meta-analysis. Plast Reconstr Surg Glob Open. 2024;12(8):e6084. doi: 10.1097/GOX.0000000000006084.