If it is for a jib,demand a urine test, and be sure to list all your medication.
I have stage 4 end stage renal failure. I am on dialysis and am diabetic too. I test positive for cocaine on an oral drug test. What could have caused this ? I don't use Illegal drugs. I also use a topical lidocane prep for neuropathy in hands and feet.
When something comes back positive on a drug screen, they usually do further screening for the specific drug in question.
Sometimes prescription drug medications, will give u a false positive.