I have always needed like 3 shots to numb me for fillings or dental extractions. I don't think I have found the same reaction with other medications but then again I take very few.
I'm totally into the genetic knowledge we continue to identify. Here is a link someone suggested for reasonably priced biomarker testing at a pharmecutical lecture I attended recently. No clue about the company itself just heard it from a fellow participant.
http://www.ilgenetics.com/content/ne.../q/news-id/241