Hair Drug Testing

Testing hair samples is a non-invasive method of providing evidence of an individual's history of drug or alcohol use. It can provide a record over a longer period of time (months rather than days) than any other sample type such as blood, urine or oral fluid.

Hair is fed by a blood supply so substances that are circulating in the bloodstream can become incorporated into the growing hair. Hair can also incorporate drugs and other substances from sweat or sebum (an oily substance secreted by the sebaceous glands that helps to prevent hair and skin from drying out) or from environmental exposure to smoke or vapour.

Our panel consists of the 9 drug groups most frequently tested for in family court cases but we are able to test for other drugs on request. If you need us to test for a drug not on our standard panel please call our Customer services team (free) on 0800 036 2522.

It is estimated to take approximately 5-7 days from the time of drug use or exposure for head hair containing the drug markers to grow above the scalp and be available for cutting and analysis. It is recommended to wait at least three to four weeks following the suspected use of a drug before collection of a sample so that the period of use/exposure is included in the collected sample.

Body hair has a similar rate of growth as head hair, with a range of between approximately 0.9 and 1.1cm per month, but it has a different pattern of growth and resting phases. It has been estimated that body hair has a much higher proportion, approximately 40% - 60%, in the resting phase compared to only 10% - 15% for head hair.

As a consequence body hair samples are not divided into sections for analysis and any use of or exposure to a detected drug may have been in the weeks prior to the sample collection or many months earlier than this.

For an accurate test we require a sample which is the approximate diameter of a standard drinking straw. This amount of hair is unlikely to give any considerable cosmetic concern to the donor.