Will 2 pills of Concerta or adderall show up on hair test?

Until that portion of the hair has grown out. Depending on how you body metabolizes those substances it could even continue to secrete it into the hair for weeks after the last use. Unfortunately people have caught on to the fact that you really can't cheat a hair test and you pretty much have to be entirely clean or shave off all your body hair, but they will know why you did that so..... basically you have to be clean and stay clean!