At first, I continued to receive treatment with the cheapest Botulex available, but after 2 or 3 years, I felt it was becoming less effective (maintenance was really bad), so I switched to Xeomin, which is a bit more expensive. You definitely feel like your jaw muscles are losing strength after 3 hours? After a while, it gets better. It's been over 2 years since I've been receiving Xeomin. They say I'm not resistant, but I feel like it's becoming less effective, so I wonder if I should stop getting Botox treatment and get it later.