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Frequently Asked Questions: Hair Testing



 1. What is Hair drug testing?

Hair testing analyzes a hair sample for parent drugs and their metabolites.  A hair specimen, collected from a donor’s head or body, is sent to the laboratory and is screened for illicit substances.


2. What drugs can be tested  with hair? 

Our basic  5-panel hair test can detect cocaine, marijuana, opiates, amphetamines, and phencyclidine (PCP).  Our Extended Opiates panel adds hydrocodone, hydromorphone, codeine, morphine, oxymorphone, 6-acetylmorphine (reflex) and oxycodone.  Additional drugs such as barbiturates, benzodiazepines, methadone, propoxyphene, fentanyl, sufentanil, tramadol, and meperidine are available in larger panels.


3. How effective is hair testing in detecting drug users?

Our clients regularly report finding five times as many users compared to laboratory based urine testing programs.


4. What time period does hair-testing cover? 

The typical length of head hair tested is 1½ inches from the root end. Since the average growth rate of human head hair is approximately ½ inch (1.3 cm) per month a hair analysis covers an approximate 90 day time frame. This time frame is an approximation only since an individual’s actual hair growth rate may vary from the average.


5. Does body hair give the same type of results as head hair? 

Body hair can be used for testing. However, while body hair is generally acknowledged as representing a more distant time frame than head hair, the approximate time period cannot be identified due to the high variability of growth rates.


6. How soon after use can a drug be detected in hair? 

It takes approximately 5-10 days from the time of drug use for the hair containing drug to grow above the scalp where it can be collected. 


7. What methodology do you employ? 

Hair samples are first screened in the laboratory using Enzyme-Linked Immunosorbent Assay (ELISA) methodology, which has been proven reliable for routine drug testing. Any samples that test presumptively positive in the screening process are then subjected to gas chromatography/mass spectrometry (GC/MS), gas chromatography/tandem mass spectrometry (GC/MS/MS), or liquid chromatography/tandem mass spectrometry (LC/MS/MS) confirmation testing.


8. How does the Laboratory establish its cut-off levels? 

The lab follows the cut-off levels generally accepted industry-wide which are similar to the cut-off levels in the 2004 proposed Substance Abuse and Mental Health Services Administration (SAMHSA) guidelines.


9. What is the turnaround time? 

Results will be available in approximately 7 days after sample is taken.


10. Is the chain-of-custody comparable to a urinalysis laboratory test procedure? 

The internal chain-of-custody is modeled after Federal guidelines (SAMHSA) as well as other accrediting agencies, such as the College of American Pathologists (CAP).


11. How long are excess hair and test reports saved? 

Any hair remaining after initial testing is completed is retained for a one year period. Test results are retained for a period of two years.


12. How is the data reported? 

Results are reported to the designated party and Medical Review Officer, if appropriate.


13. Does the Laboratories wash the hair prior to analysis? 

All hair specimens are washed prior to confirmation testing to remove possible external contamination. All wash procedures were reviewed by the FDA as part of our 510(k) clearances.


14. Can external exposure to drugs (marijuana smoke, crack smoke, etc.) have an effect on the hair test results? 

Along with a wash procedure, the lab looks for both the parent drug and metabolite (bi-product) of drug usage (where appropriate). For marijuana analysis, the lab detects only the metabolite (THC-COOH). This metabolite is only produced by the body and cannot be an environmental contaminant.


15. Can a hair test be beaten/adulterated? 

At this time there are no known successful commercial adulterants for hair tests and the recommended use of normal hair care products/procedures (shampoos, dyes, permanents, relaxers, bleaches) do not have a significant effect on results. The effects of these products were reviewed by the FDA as part of our 510(k) clearances.


16. Does hair color effect results? 

Hair color is determined by the amount of melanin in the hair. It has been shown experimentally, through actual hair samples, as well as determined in court that hair color has no significant impact on results.


17. Can hair collected from a brush be used? 

Yes, but the test will be reported as having an "anonymous" donor. We cannot attribute the sample to any specific person and we cannot determine the time frame of the test, so the test result is not legally defensible.

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