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Rochester, NH
A 18-year-old male asked:

Would i pass a thc hair follicle test if i smoked marijuana once. it was once in july and i won't have the test until at least the end of october?

1 doctor answer2 doctors weighed in
Dr. Lois A Freisleben-Cook
Pediatrics 36 years experience
Possibly no: The hair follicle test is standardized to collect a specimen dating back about 90 days. Depending on how fast your hair grows, you could possibly test negative if a specimen close to the scalp is obtained.
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Last updated Jul 26, 2018

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