I seem to have a very high tolerance to lidocaine. i have never done drugs. what could cause this?

Rapid metab?: Some people are rapid metabolizers of amide type local anesthetics like lidocaine. A simple genetic test (buccal swab) would give you the answer. People do not usually develop a tolerance to lidocaine. There are many other choices for local anesthesia. The Ester class of LA could also be used. Like any other medicine it is based on weak science and trial and error. The Art of Medicine!

Strength of dose/typ: Lidocaine ( Xylocaine ) comes as both 1% and 2% Other options would be a stronger local anesthesia such as mepivicaine or pontocaine.

Metabolism: We do not know exactly why, but some people metabolize substances much faster than others. It seems to have to do with the genetics of the enzyme systems in the liver in most cases.