Can using 2 different neurotoxins at 1 appt (e.g. Botox & Daxxify) increase or decrease the risk of resistance?

Hey there! This is Dr. Kotecha. I love this question because I get it often from patients who are curious about switching up their neurotoxins.
The short answer? Using two different neurotoxins (like Botox & Daxxify) in one session isn’t likely to increase or decrease your risk of developing resistance. But let me explain why.
Resistance to neurotoxins happens when your body builds neutralizing antibodies against the active ingredient (botulinum toxin type A). This is rare, but when it does happen, it’s usually due to high doses, frequent treatments, or exposure to complexing proteins found in some formulations.
I actually use Daxxify and Botox (or Xeomin) in the same treatment quite frequently based on my patients’ goals, budgets, and how long they want their results to last. Some patients want the longevity of Daxxify for their frown lines but stick with Botox for medical reasons like TMJ or migraines. Others prefer Xeomin because it’s a “naked” toxin (without extra proteins) and may have a lower risk of resistance in the long run.
That said, there’s no strong evidence that using multiple neurotoxins at the same time will impact resistance much. Since they all share the same active ingredient, your immune system isn’t likely to treat them too differently.
What really matters is how often you’re getting treated, the total dose over time, and whether your body is prone to forming antibodies. If you’ve been on Botox for years and are noticing it’s not lasting as long, that might be a sign to try another brand. Otherwise, using two in one session isn’t a major factor in resistance.

Mixing different neuromodulators such as Botox or Xeomin will not create resistance to any of the products. Resistance is a naturally occurring reaction.