20 units of Botox is a good standard dose. It is also a good starting point for someone who was never had anything in the glabellar region before. I often try to differentiate what to expect in terms of 11's deepening while you frown versus 11's at you see when you're not frowning at all. Botox...
The good news is that Botox always wears off and muscle function returns to normal if it was a result of the Botox. Usually the unwanted effects do not last the entire time of the normal treatments. Looking in the mirror and trying to force the normal movements sometimes help things...
These lines can take some time to appear improved after Botox injections, typically from 1-2 weeks. After that period of time if you do not see improvement you may need additional injections.