Hair drug testing is now a mature technology which offers significant advantages over the use of urine testing in certain circumstances. In particular, the long drugs of abuse surveillance period and the difficulty of evasion, even in the absence of oppressive security precautions, offer substantial advantages in a forensic setting. Hair-testing is a useful tool, but it is essential that any testing regime be integrated into an appropriate clinical treatment and management plan for the individual patient.

1 It should be noted that urine tests can also provide false positive results. For example, eating poppy seeds, sometimes sprinkled on bread buns, may result in a positive urine test for opiates, but is shown not to result in a positive hair test, because of the higher cut-off levels used for reporting a positive result in hair-testing (Baumgartner & Hill, 1996).