A typical hair test will check for the five most commonly used illegal substances.  They are marijuana, cocaine, opiates, PCP and amphetamines (methamphetamines/ecstasy).  Because most illegal drugs besides marijuana can be out of your system in a few weeks hair testing is a more accurate diagnosis of your intake over a longer period of time.  In referring to drugs being “out of your system” this means that they can no longer be detected in urine tests, saliva tests or even blood tests after a few weeks for a single use or a small dosage.

Because there is blood flow into the hair follicle and no blood flow out of the follicle, the drug metabolites remain in the inner cortex of the hair follicle until they grow out and are removed by cutting away the part of the hair containing the metabolites.  Once your blood is clean then any new hair growth will be clean as well.  Your hair is a dead element that sits outside of your body and has no liver or kidney to act as a “cleanser” of the impurities in your body.  As such, the hair test is used as a more accurate barometer of long term drug use.  With a saliva test, the metabolites from certain drugs can past their detection period in a matter of hours and with a urine test those same drug metabolites can be past their detection period in a matter of days or weeks.  Not true with a hair test where the same metabolites can be detected months after ingestion.

(To Be Continued)