Hair drugs of abuse testing offers up to a 90-day window for detection of drug use1 prior to the test date and a convenient collection process that can be performed almost anywhere.
The collector obtains a 100-milligram sample of hair (90 to 120 strands) cut at the scalp. The collector secures the hair sample in foil and completes chain of custody documentation in preparation for shipment to the testing laboratory. Since hair samples are obtained in full view of the collector, the process minimizes the likelihood of sample adulteration or specimen substitution. Labcorp offers hair specimen collections in many of our specimen collection sites located throughout the United States. Our extensive network offers your employees convenient access to a Labcorp collection site.
Labcorp offers initial screening tests performed by enzyme-linked immunosorbent assay (ELISA) with confirmation of presumptive positive screens by gas chromatography/tandem mass spectrometry (GC/MS-MS) or liquid chromatography/tandem mass spectrometry (LC/MS-MS). Results for specimens that screen negative for all drugs are generally available within 48 to 72 hours after specimens are received at the laboratory. Results for confirmation testing of presumptive positive screens are usually available within an additional 72 hours.
To set up a hair drug testing program, contact Labcorp sales.
Drug detection times vary depending on the dose, sensitivity of the testing method used, preparation and route of administration, duration of use (acute or chronic), the matrix that is analyzed, the molecule or metabolite that is looked for, the pH and concentration of the matrix (urine, oral fluid), and variations in metabolic and renal clearance.2 In general, the detection time is longest in hair, followed by urine and oral fluid.2 Drugs in hair may be detectable for approximately 90 days, whereas drugs in urine are generally detectable for one to seven days or longer in chronic users and in oral fluid from five to 48 hours.2
Hair growth rates vary; typically, head hair grows at an average of one-half inch per month. Therefore, a 1.5-inch hair sample detects drug use up to 90 days prior to testing.1
A hair drug test with initial screen and confirmation requires 100 milligrams of hair (90 to 120 strands).