Hair drug testing is a technique used for detecting drug use by examining hair samples for drug metabolites. With a one-inch hair sample containing about 50 hair strands, labs can detect the use of drugs within the past two months. If you have very short hair, labs are able to take a sample from any part of the body. Hair drug testing is widely used in the casino industry. People with dark hair are 10-50 times more likely to test positive for drug use from a hair follicle drug test due to the different makeup of dark hair versus light hair.
During hair follicle drug tests, drugs deposited in hair can be measured by radioimmunoassay and ultrasensitive gas chromatograph/mass spectrometry procedures. Hair follicle drug tests can detect Marijuana, Ecstasy (MDMA), Cocaine (including crack), Opiates (including heroin), Methamphetamine, and Phencyclidine (PCP or angel dust).
If you want to pass a hair follicle drug test, you must utilize a hair follicle shampoo that removes all drug residue from the hair follicles prior to giving the hair sample. Quality hair follicle drug detox products completely remove the drug residue from your hair and will guarantee that drug residue will not return to the hair follicles for at least 8 hours after the hair shampoo and cleanser are used.