Dear Linda
While these products are both types of botulinum toxin A, they are not exactly equivalent. There are definitely not "generic" versions of each other. When you go the drug store and you see the brand name over the counter antiacid and the drug store's generic version, these products have a very specific relationship as required by the FDA. This relates to the concept of bioequivlance. To be generic, the generic product and the brand product need to have a dose and therapeutic effect within 90% of each other. While this is a simplication it gives you a feel for how close a generic and brand product are when they are bioequivalent. BOTOX and Dysport are not bioequvalent. Even though they are both botulinum toxin A products, they are not equivalent. First the relative stength of BOTOX to Dysport is thought to be about 2 to 4 depending on the particular application. Also Dysport diffuses more widely than BOTOX. Regarding longevity, there is not meaningful evidence that there is much difference. These differences mean that doctors will need to become accustom to how to use Reloxin (the name underwhich Dysport will be marketed in the United States),
