I had Botox many years ago right after it came out. The result was amazing. Unfortunately, I couldn't afford it for awhile so I never went back. About a year ago I decided to try it again.
I went back to the same dermatologist several times because the furrow was not smooth at all. He had taken before pictures in which he made me furrow my eyebrows as hard as I could, then he used these pictures to try to tell me I looked great. I was disgusted as he had been written up in the NY area as being the BOtox KING. I waited until recently to try again with a plastic surgeon. I told him my story. He said he "just didn't use enough".
I had the injections with some initial smoothness but a few weeks later I was completely able to furrow that brown again, He gave me more and said "I've given you a huge dose" this should do it. I still see the line. I've read that some people are trying the restylane for this area. I think I'm immune.