If someone has been clean from all drugs for 9 months but then smokes crack for one night can they pass a hair follicle test after two months?

Depends on how long his hair is. As it seems you know, any injested drug leaves a trace in ones hair. Concerning testing: Most testing facilities only use hair within about 1 1/2 inches of the scalp, and get rid of the rest. This limits the detection of any drugs to about 90 days, depending upon the rate of growth of the persons hair. Studies indicate that hair taken from the crown of the head grows on the average of approximately 1.3 cm (or 1/2 inch) per month. So I would assume that nine months would definitely be enough time. If you are really worried cut your hair real short leaving enough for them to test but if there isn't enough on your head than other body hair can be used. Good Luck!!

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