11 doctors weighed in:

How far back does an oral drug test detect cannabis?

11 doctors weighed in
Dr. Horacio Capote
Psychiatry
10 doctors agree

In brief: Depends

Since thc (the active ingredient in marijuana) binds to fat, it depends on you much fat you have, how much you use, & how physically active you are.
It would not be unusual to test positive for a month.

In brief: Depends

Since thc (the active ingredient in marijuana) binds to fat, it depends on you much fat you have, how much you use, & how physically active you are.
It would not be unusual to test positive for a month.
Dr. Horacio Capote
Dr. Horacio Capote
Thank
1 comment
Dr. Martin Raff
You do not actually have to smoke it, but just being in a room where there is smoke can result in inhalation and tissue absorption which will persist for weeks.
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