Xeomin is a type of botulinum toxin a, and is essentially the same in its effect to Allergan's "Botox." It does work well for lip wrinkles, but keep in mind that just like a piece of paper that has been folded the lip skin creases can be smoothed but will still show some crease on them. The botulinum toxin can help with the wrinkles, but many patients benefit further with a dermal filler (e.g., restylane, juvederm, belotero) and sometimes a chemical peel or laser resurfacing of severe lip rhytids (wrinkles). The dermal fillers help fill in the creases and enhance lip volume, which can further improve the wrinkles. Generally I don't have to give more than 12-15 units of botox to the lips themselves, but if you get some to your lip depressor muscles then you could easily get up to the 20 units. The botox has to be placed carefully in the lips to avoid lip sagging or unevenness of strength to avoid drooling etc. Going forward avoid smoking, drinking out of straws, and pursing your lips excessively to help keep your lips smooth. Best regards.