What is a segmented drug test?

A segmented drug test is a type of drug test performed on an individual’s sample of hair that permits a month-by-month profile of drug use to be attained. It works by measuring the drug molecules embedded inside the hair shaft.

The sample of head hair is ideally cut from the individual’s highest point of the scalp, called the vertex, as this region is associated with least variation in growth rates. The sample needs to contain around 200 individual strands (about the width of a pencil). This sample is then segmenting into 1-cm sections. This is because head hair grows at an average rate of 1 cm each month. Therefore, by cutting it into 1-cm sections drug use can be established over a defined period depending on the length of hair selected. For example, if a segmented drug test was to cover 6 months, a month-by-month analysis will provide six individual results for each of the months.

AlphaBiolabs’ standard drugs panel for a segmented drug test includes amphetamine, benzodiazepines, buprenorphine, cannabis, cocaine, ecstasy (MDMA), ketamine, mephedrone, methadone, methamphetamine, opiates, phencyclidine and zolpidem. A segmented drug test can also be arranged to test for other drugs, including GHB, LSD, Spice, steroids and Tramadol.

What are the benefits of segmented drug tests?

A segmented drug test can be used to pinpoint the actual month in which the episode of drug taking occurred. In this way, by analysing each monthly segment of hair, it is possible to obtain a trend in drug use. This can show a decrease or increase in drug use over time, or even highlight intermittent drug use.

How does a segmented drug test work?

When the hair samples arrive at AlphaBiolabs laboratory, each section is chemically washed three times. This is to avoid any false positive results should an individual have been in an environment heavily laden with a drug. In this way, any detectable levels found on the hair sample due to smoke or direct transfer (such as by hands) is removed prior to analysis. The segmented hair samples are then examined using a powerful analytical tool called liquid chromatography with tandem mass spectrometry (LC–MS/MS). This enables AlphaBiolabs to confirm and quantify the presence of illicit drugs and their various metabolites.

AlphaBiolabs also offers an overview hair drug test, which is useful to obtain a general indication of drug use. In this type of hair drug test, any episodes of drug taking are averaged out over the period being tested. The company uses a UK-wide network of sample collectors who can collect samples from an address of your choice. These experienced sample collectors ensure that the head hair sample is taken from a discreet area whenever possible. For further information on segmented hair drug testing and other drug testing solutions, please call our Customer Services team on 0333 600 1300 or email us at