Is Botox safe for a sensitive person with allergies?

I'm a 47 year old female considering botox for the "11" lines between my eyebrows, but I have a extremely sensitive body. I allergic to food preservatives like MSG, caffeine where I get severe migraines. I don't know if this makes a difference but I have issues with NOT sweating very much and I have a rare blood type AB+. Otherwise, I'm in great health. I'm afraid I'm going to have a bad reaction. Please advise. Thank you.