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Fastest Labs Energy Corridor & Katy Change Location

Blogs from April, 2019


What is a hair drug test?

Hair testing analyzes for drugs within the hair shaft, rather than body fluids like urine or saliva, to determine whether drugs of abuse are present. Compared to analysis of body fluids, hair testing is highly resistant to evasion by adulterating or substituting samples, or by simply abstaining from drug use for a few days.

We have answered some frequently asked questions regarding hair drug testing:

How much hair is cut for a hair testing drug test?

A cosmetically undetectable lock of hair preferably snipped from the back of the head, just below the crown is required for a hair drug test. In general, the amount needed equates to a single row of hairs approximately one centimeter wide or the thickness of a pencil lead.

Can a donor cheat a hair test?

We have not found any adulterants that can beat the test at this time. Moreover, the risk is minimized because every collection is directly and easily observed. In addition, commonly used hair procedures (e.g., shampoos, conditioners, sprays, mousses and gels) have no significant effect on results.

Can tests be run on people with little or no hair?

Yes. Hair can be collected from several locations on the head and combined to obtain the required amount of hair. If head hair is not available, certain body hair can be used as an alternative.

Will the test results from a hair test really reflect drug use over the past 90 days?

Yes. Hair follicles underneath the scalp are surrounded by a dense network of capillary blood vessels. Drugs in the bloodstream are able to incorporate and bind to the hair follicles underneath the scalp. It takes approximately 5 to 10 days for hair containing drug to reach the outer environment on top of the scalp to be collected based on the average rate of head hair growth. Head hair grows approximately 1.3 cm or a ½ inch per month. The standard length of hair tested by the laboratory is the first 3.9 cm or 1½ inches from the root end. Therefore, a hair analysis of 3.9 cm covers a time span of approximately 90 days and detects a pattern of drug use over this time frame. Many employers find it useful to test both hair and urine (or oral fluid) for pre-employment purposes. Urine (or oral fluid) is useful for detecting recent or new drug use (the last one to three days) and hair for providing an approximate three-month drug history of repetitive use.

Call us to schedule an appointment today for personal hair drug testing. All test results are 100% CONFIDENTIAL at Fastest Labs.

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