Ok guys so about 3 weeks ago I took two hits of pot from a buddy. First time for me to smoke in well over a year. I have very short hair and actually just cut it today. What are the chances of passing a follicle test that I may have to take in the coming weeks for a prospective job.

Light use is seldom detected. “Positive results from hair testing are generally expected only when a person has used a drug at least four to six times per month” [This applies to drugs in general and not just THC] (1)

Hair is a particularly poor medium for THC (cannabis metabolite) as it "is not strongly bound to melanin, resulting in much lower concentrations of THC in hair as compared to other drugs of abuse." (2)


Galanter & Kleber, 2011 Psychotherapy for the Treatment of Substance Abuse, American Psychiatric Publishing, Wash, DC, p. 58

Marilyn A. Huestis (2007) Human Cannabinoid Pharmacokinetics. Chem Biodivers. 2007 August; 4(8): 1770–1804. Sec 3.5