You can always tell whether there is a definitive answer in medicine when everyone answers the same way. And if you get lots of different answers, you know that the jury is still out. A couple of years ago, I reviewed your question for my own needs. The bottom line is that the best starting dose is 50 units per palm. Dilution was not critical, but most studies use either a 4 cc dilution or a 5 cc dilution. Any dose less than that, and you may suffer from incomplete resolution or compromised duration. I also appy a topical anesthetic cream to the area for a half an hour prior, which makes it quite tolerable. The largest body of literature supports the numbers mentioned above. And as Dr Lupo notes, some patients may still need a little more but it is rare. And in fact has not happened in my practice thus far.