How does drug testing using hair work?

Hair testing is quite accurate and can go back normally 3 months (6 months or longer possible with specialty tests) showing any drugs of abuse used in the detection window. As hair grows out, any drugs used are encased in the hair shaft, so the longer the hair, the longer back in the individual's drug history the lab can detect. Accredited hair drug testing labs, however, only use hair within about 1.5 inchs (2.5–4 cm) of the scalp, and discard the rest. With head hair each 0.5 inch (0.8 cm) corresponds to about 30 days. This limits the detection history to about 90 days, depending upon the rate of growth of the individual's hair.

[Source] [Related Link]

Keywords: hair test hair follicle hair shaft

Back To Drug FAQ

Home My Account Order Status Contact Us About TestCountry Sales & Partners Corporate Accounts Affiliate Program

Information TestCountry Resources Health & Drug Testing Information Center Drug Slang & Street Name Search Local Drug Testing Centers Health Testing & Drug Testing Guides, Reviews, Information & Facts Support Store Policies FAQ