Hair strand testing for drugs

Drug testing can screen for the use of illegal drugs, as well as the misuse of prescription medications, over-the-counter medicines, and legal substances including alcohol and tobacco.

There are various methods we use to test for drugs.  Hair strand drug tests identify drugs or their break-down substances in a sample of hair and is a non-invasive, painless and reliable procedure..

Once a drug is consumed, it enters the bloodstream and travels throughout the body.  Scientists can analyse hair samples to detect these trace amounts of drugs and their metabolites, which are substances produced by the body when a drug is taken and can be used to show drug use.    A laboratory analysis can then provide an interpretation of the levels of drugs detected.

During hair strand drug testing, scissors are used to remove a small sample of hair.   While drug use and misuse may not actually appear in the hair until 7 to 10 days after drug exposure, once it enters the hair it remains for weeks, months, or even years.   

How long drugs remain detectable in hair is called the ‘window of detection’. The length of the detection window varies based on a number of factors, including the amount and frequency of drug use or misuse and the rate at which the drug is metabolized in the body. Some drugs continue to enter new hair growth for months after a person’s last drug exposure.

The window of detection also varies based on the amount of hair tested. Although longer samples of hair can be tested for drug exposure over a longer period of time, a standard sample of hair from the scalp is 1.5 inches and provides information about approximately 90 days of past drug exposure.   So roughly, 1cm = 1 month.   A hair sample taken from a different part of the body where hair grows more slowly may have a detection window of up to 12 months.

The cost of the testing can vary so shop around.