I'd post that one on the Concealed Carry sub forum but you could go to a sheriffs dept. and have them run a background check on you, (there will be a fee, I think), and see if anything shows up that would disqualify you from getting a carry lic. BEFORE you take the class.
Don't know why it would be in your system....the drug, that is......unless your , well.......
Are you around somebody who uses? None of my business or judging, just sayin'.
They say the best "Home Remedy" for "tyranny" is....."LEAD POISONING".