We just finished a study comparing Botox and Xeomin last year and presented it at the Boston PS Meeting in November. We found the two products 100% identical in onset and duration.What we did not expect, was the variation in duration among the patients. Conventional wisdom in the early 90s when we first experimented with Botox, was that it lasted 3 mos.When patients told us that their Botox lasted 6 months or more, I dismissed it as wishful thinking because if the neurotoxin was not metabolized, new nerve growth was supposed to replace the blocked nerves in 3 to 4 months.NOT SO! In ten patients, we had variations from 2 1/2 months to 7 1/2 months with the majority between 3 and 4 months.Everyone was different with same dosage and administration!Metabolism cannot be accelerated but it will wear off. Be patient, and do not let anyone inject your lips again.