CBD and drug testing – does CBD show up on drug tests?

The use of cannabidiol (CBD) is on the rise in Ireland, with advocates of CBD turning to these products as an alternative treatment for a range of conditions including anxiety and insomnia.

But what exactly is CBD? In this article, we explain CBD, why people use it, and whether CBD will show up on a drug test.

What is drug testing and how are drug tests performed?

When a person uses drugs, a proportion of the drug and its metabolites are released into the bloodstream, with a small amount being excreted by the body in a variety of ways.

This makes it possible to analyse a variety of samples for the presence of drugs including hair, nails, saliva (oral fluid) and urine.

Even after the ‘high’ has worn off, drug use can be detected by a drug test long after the drug was first consumed, depending on the type of test you take.

The most common types of drug test include urine drug tests, saliva (oral fluid) drug tests, hair drug tests and nail drug tests, with each offering a different insight into a person’s drug use.

Oral fluid tests can detect drugs for up to 48 hours, while urine drug tests can detect drugs and their metabolites up to four days after drugs were consumed.

The rate at which head hair grows means that head hair drug tests provide a wide window of detection for drug use, making it possible to detect metabolites in the hair for up to 12 months after drug use, depending on the length of the hair.

Similarly, nail drug testing can be used to provide an overview of up to 12 months for drug use (six months for fingernails and 12 months for toenails). 

What is CBD and what is CBD used for?

Cannabidiol or CBD, is a chemical found in cannabis.

However, unlike cannabis, CBD produces few if any psychoactive effects. This is because CBD only contains small amounts of tetrahydrocannabinol (THC) – the psychoactive ingredient in cannabis.

It is typically sold online and in select shops in the form of CBD oil but can be found in liquid form or as an oil-based capsule.

Although legal in Ireland, CBD products are heavily regulated, and must contain less than 0.2% THC when sold online or over the counter.

Although rare, cannabis-based medicines including CBD may be prescribed in Ireland on a case-by-case basis to relieve symptoms of certain conditions, where standard therapies have failed.

People with the following conditions may be eligible for access to medicinal cannabis:

  • Multiple sclerosis
  • Nausea and vomiting associated with cancer treatment (chemotherapy)
  • Severe, treatment-resistant epilepsy, where anticonvulsant medications have not worked

What is the difference between CBD and THC?

Although both cannabidiol (CBD) and tetrahydrocannabinol (THC) derive from the Cannabis sativa plant, and are classed as cannabinoids, there are some differences between the two.

THC is the main psychoactive ingredient found in cannabis and is responsible for the ‘high’ that people experience when using cannabis.

Unlike THC however, CBD produces few if any psychoactive effects.

THC that is used recreationally or for non-medical purposes is illegal in Ireland and is controlled under the Misuse of Drugs Act 1977. However, CBD products are legal in Ireland – albeit subject to heavy regulation.

For CBD products to be legally bought and sold in Ireland, they must be hemp-derived and contain less than 0.2% (trace levels) of THC.

When used in medical settings, both THC and CBD can be prescribed to treat certain conditions including epilepsy, multiple sclerosis (MS), and nausea and vomiting in adults undergoing chemotherapy, where other treatments have previously failed or been unsuitable.

Does CBD show up on drug tests?

When a drug test is used to detect cannabis, the sample will be analysed for the presence of tetrahydrocannabinol (THC – the psychoactive ingredient in cannabis) above certain cut-off levels.

CBD products sold in Ireland must contain less than 0.2% THC to be sold legally. This means that legally compliant CBD products will only contain very, very small amounts of THC.

For this reason, it is unlikely that a drug test could detect the use of CBD.

Unfortunately, however, not all CBD products in Ireland are regulated. Some unscrupulous retailers have been known to sell CBD products containing much higher levels of THC than permitted under Irish law.

In these circumstances, the person using them could test positive for THC on a drug test.

If you are due to undergo a drug test and are currently using CBD products, either prescribed or purchased online/over the counter, we strongly advise you disclose this information before undergoing a drug test.  

What are the different types of CBD?

Cannabidiol (CBD) comes from the cannabis plant, but different plants have their own compounds and chemical compositions, as well as varying levels of THC.

CBD products are available in three forms:

  • Full-spectrum CBD: containing all the compounds that naturally occur in cannabis plants, such as flavonoids, terpenes, and cannabinoids including THC.Full-spectrum CBD products such as oils, creams and edibles may contain trace levels of THC. However, to be legally sold in Ireland, they must contain less than 0.2% THC.
  • Broad-spectrum CBD: as with full-spectrum CBD products, these products contain compounds from the cannabis plant including cannabinoids and terpenes.However, in broad-spectrum CBD products, the THC has been removed. Commonly sold as an oil, these types of products are very unlikely to contain THC.
  • CBD isolate: these products contain pure CBD and do not have any additional compounds from the cannabis plant. Known as hemp-derived CBD, these products should not contain any THC.

Will CBD cause a false positive on a drug test?

A drug test will only provide a positive result if certain drugs and their metabolites are detected in a person’s sample.

In instances where CBD is being used, a positive reading will only occur if there is indication of THC in the person’s system above a certain level.

There are a few different reasons why using CBD could result in someone failing a drug test, including:

  • Cross-contamination during the manufacturing of CBD products
  • Second-hand exposure to THC (e.g. via second-hand smoking of cannabis)
  • Using unregulated products (e.g. CBD products containing levels of THC above the legal amounts. CBD products sold in Ireland must contain less than 0.2% THC)

How to avoid testing positive when using CBD

Because drug tests for cannabis look for the presence of tetrahydrocannabinol (THC) – the psychoactive ingredient found in cannabis – it is unlikely that legally-compliant CBD (containing less than 0.2% THC) would be detected during a drug test.

Furthermore, reputable testing laboratories like AlphaBiolabs can distinguish between THC that is present due to cannabis use, and CBD.

Although there would be little need for someone to attempt to cheat a drug test while using legally compliant CBD, some people do still try to cheat drug tests when using CBD products.

Some of the methods people try include:

  • Using another person’s ‘clean’ urine sample
  • Wearing a wig to prevent hair samples from being collected
  • Using someone else’s hair sample as their own
  • Cutting their nails short to avoid providing samples for testing

Fortunately, testing laboratories like AlphaBiolabs are fully equipped to spot the signs of sample tampering when performing drug testing.

Where can I get a drug test?

Our Home Drug Testing Kit has been designed to give you peace of mind or enable you to seek support for a friend or loved one who is struggling with substance misuse.

This easy-to-use, self-contained screening kit can detect drugs and their metabolites in a urine sample, with built-in test strips that allow you to read the results in just 5 minutes

Please be aware that our home drug test kits are for peace of mind only, and the results cannot be used in court. If you require a drug test for official matters, you will need a legally-instructed drug test.

For confidential advice about which test might best suit your needs, you can also call our Customer Services team on 01 402 9366 or email

Home Drug Testing Kit

Buy your easy-to-use home drug test kit online now for just €20.

Gail Evans AlphaBiolabs

Gail Evans

Technical Trainer at AlphaBiolabs

A professionally-trained forensic scientist, Gail joined AlphaBiolabs in 2012 and holds the role of Technical Trainer.

Her day-to-day responsibilities include delivering in-depth training sessions both internally and externally, covering DNA, drug, and alcohol testing.

Throughout her career at AlphaBiolabs, Gail has held a variety of roles, including within the Legal and Workplace sectors of the business.

Before joining the company, Gail was a practicing forensic scientist with 25 years’ experience working for the Forensic Science Service, attending scenes of crime, and analysing physical and biological material with potential evidential value.

Gail also holds qualifications in chemistry and is a Lead Auditor for the ISO 9001 standard, the international standard for quality management.

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