How Accurate Are Cannabis Drug Tests?

A question we are always asked at Zoom Testing is “How accurate are your cannabis drug tests?” We get asked this question quite regularly from people in all sorts of situations. A common scenario is that a person is scheduled for a drug test at work. For one reason or another, they have been using cannabis and are worried that a positive drug test will get them the sack. So they buy one of our tests beforehand to check that they are okay before the real test at work.

If our customer taking the drug test gets a negative result, they are often overjoyed. But then the doubt kicks in. Just how accurate was the test? Is it possible that I will get a positive at work, when I got a negative on the home test?

In short, there is no need to worry. Generally, a drug test from us will give similar results that of an employer drug test. How far the drug tests can check for, is based on the type of test it is – either urine, saliva or hair follicle testing.

How accurate are urine drug test kits for Cannabis?

Modern day drug tests are very accurate. Typically, most drug testing kits will have an accuracy of between 97 and 99% when the manufacturers instructions are followed correctly. This is very high. Because most employment drug screening uses urine drug tests, it means that they are very hard to cheat.

Many will attempt to cheat a cannabis drugs test by one of three methods: substitution, addition or dilution.

The first method means that a drug test for cannabis can be beaten by substitution of the donor’s urine with that of anther person who is “clean” of drugs. Sounds simple, but it is not that easy! Often urine that is donated as part of a drugs test is subjected to an adulteration test. These kinds of tests are designed to identify instances where fake urine has been used in a drugs test.

Addition or dilution is when the urine sample is watered down or chemicals are added to the urine sample to try and produce a negative result. Once again, an adulteration test kit will show if the urine sample has been tempered with.

Urine drug tests for Cannabis are normally single drug test kits or one drug that is tested for as part of a multi-drug test kit.

How accurate are saliva drug test kits for Cannabis?

Many employers are now turning to saliva drug tests as a way of drug testing for cannabis. Tests that use saliva are often preferred now as they are much harder to cheat than urine drug teats. They also have less privacy issues, Accuracy of saliva drug tests for cannabis are also high, up to 99%. However the testing window for saliva drug test kits is much lower than urine tests.

Saliva drug tests for cannabis are normally multi drug test kits that test for a number of drugs at once, of which cannabis is just one

How accurate is hair drug testing for cannabis?

Hair drug testing for cannabis is very reliable. Hair samples can be tested and results can be obtained for drug usage up to 90 days after the event with a high  level of accuracy.

Which brands of  drug test kits for cannabis are the most accurate?

Zoom Testing only offers and sells drug test kits from reputable drug test manufacturers around the world. All tests are CE marked and quality assured.

Best Cannabis Drug Testing Kits

cannabis drugs test

Cannabis Drug Test (THC)

Professional cannabis urine drug test kits. These single use cannabis drug test cassettes detect THC in urine at a cut-off of 50 ng/mL. Zoom Testing cannabis drug tests are 99% reliable and give results in less than 5 minutes. This product is used to obtain a visual, qualitative result and ... Read More

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3 Panel Drug Test Kit

3 Panel Drug Test – Urine – Type E

These 3 panel multi drug test kits are designed for qualitative determination of drug substances in a sample of urine. It is designed to detect the presence of Amphetamine (AMP), Cocaine (COC) and Cannabis (THC). The drug test kit analyses specific compounds in a human urine specimen.The test gives easy ... Read More

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Cannabis Drug Identification Test

10 Ampoule Pack ... Read More

£29.99 £24.99
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Spice Drug Test

Spice Drug Test

These urine drug test kits from Zoom Testing are designed to detect Synthetic Cannabis, commonly know as Spice or K2. The drug test is designed to be easy-to-use, and to give 99% reliable results in less than 5 minutes. Test in the convenience of your own home or office. Easy ... Read More

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This post has been updated since its original publication in 2015.

Photo Credit: “Joint Stuff” (CC BY 2.0) by halseike