Dr.Bill,

I have read almost all of your posts on this subject and I am like everyone else that would be reading such things in that I have consumed marijuana recently and will be subject to a HDT in a couple of days. I have two questions that I would like your opinion on. 1) How can I be sure the lab testing my hair will only be testing for THC-COOH. If I understand correctly, this is the only metabolite that can't come external exposure? 2) I have smoked 4 times in the last 90 days averaging about 6 hits each time. I spoke to someone at the testing site and they said they take 1" hair samples (so I assume that will go back 60 days) The heaviest smoke session was almost 90 days ago. What are my chances of a negative result?

Incidentally, I had someone I know call the actual lab doing the testing and an executive at the lab said that hair testing will not catch someone who just smokes every other weekend.

Any drugs used stay in the hair follicles.

Dr. Bill is on hiatus until at least January.