Hair Drug Testing

Hair drug testing, like no other drug testing, shows a history of chronic abuse. Urine drug testing is better for showing recent abuse. Both tests can be used together to provide a better picture of the overall situation. 

A standard drug test performed on a hair specimen is usually a 5 panel test, however, it is also possible to test for additional drugs such as oxycodone, hydrocodone or hydromorphone. The specimen taken is usually cut as close as possible to the scalp. The first 1 ½ inches of the hair is tested.

In regard to the time frame of hair tests, it is important to note that hair grows at approximately ½ inch per month.  It takes hair approximately one to two weeks to grow from the hair follicle through the scalp to a level above the scalp accessible to scissors. The first 1½ inches of hair cut off from the scalp is tested by the laboratory, therefore, a hair analysis of 1½ inches goes back approximately 90 days.

Because of the relative slow growth of hair, a single use of a drug will not typically be detected during a hair analysis.  Hair testing is best used to the answer the question “Did the subject chronically use a drug within the past X months?” (X represents the length of the hair tested).

If the donor’s hair is long enough, you can test back for longer periods of time than the standard 90 day test. These are representations of the approximate length(s) of hair needed to test various time periods:

Each 3 months section is a separate hair test.

All positive results are confirmed by GC/MS .

Environmental Exposure Hair Test

This is a very sensitive hair test which shows whether there has been passive inhalation of a substance or ingestion of drugs at a much lower dosage than a standard hair test. 

Environmental Exposure can be used to determine the following: