Are they actually different drugs?
Yes they are different, but only slightly.
Both Botox and Dysport are made from the same active ingredient: Clostridium botulinum toxin type A. Botox is Onabotulinum toxin A and Dysport is Abobotulinum toxin A. The toxin affects the nervous system, relaxing the muscles in the area where it’s injected and preventing them from creating the creases and wrinkles they would otherwise form.
In terms of actual structure, there is one main distinguishing factor between them: Dysport molecules are smaller than Botox molecules. This means that Dysport has a different diffusion rate and has a tendency to spread farther from the site where it was injected than Botox does. The way their units are measured is different too, which brings us to our next question !