Changes to Random Roadside Saliva Drug Testing in NZ: What it Means for Medicinal Cannabis Patients

The rules around drug driving in New Zealand are changing, and if you’re a medicinal cannabis patient, it’s important to know what this means for you. While these new laws aim to make roads safer, they also raise concerns for patients who use prescribed cannabis products. Here’s a simple breakdown of what you need to know.

What is the New Law?

The Land Transport (Drug Driving) Amendment Act 2022 has passed its third and final reading in Parliament and is now awaiting approval from the Governor-General before becoming law.

Once enacted, police will be able to conduct random roadside saliva drug testing for certain substances, including THC – the compound found in some medicinal cannabis products.

If you’re pulled over, you may be asked to take a saliva swab test. If the test detects THC, you will need to take a second test straight away. If both tests are positive, you will be required to immediately stop driving for 12 hours.

Your saliva sample will then be sent to a laboratory for confirmation. If the lab results confirm the presence of THC above the legal threshold, you could receive an infringement notice, which may include:

• A $200 fine
• 50 demerit points on your licence

Important: Saliva tests may also detect THC from full-spectrum CBD products, as they can contain trace amounts of THC.

Blood Tests: What You Need to Know

If you refuse the saliva test or if police have reason to suspect you are impaired, they may require a blood test. Unlike saliva tests, which detect recent use, blood tests measure THC levels in your system over a longer period. The “high-risk” threshold for blood THC levels is 3 ng/mL, which is relatively low. If your blood test exceeds this limit, you may face more serious penalties, including:

• A $4,500 fine
• Up to 3 months in prison
• A mandatory 6-month licence disqualification

This is why we strongly advise against opting for a blood test unless absolutely necessary. 

Why Do We Need Roadside Drug Testing in NZ?

Driving under the influence of drugs has always been a major road safety concern. The approved bill seeks to test for the present of a range of drugs and medications and serve as a deterrent, thereby decreasing the rates of driving under the influence of these drugs.

Currently, New Zealand police use a compulsory impairment test (CIT) if they suspect someone is driving under the influence. However, they need a ‘good cause to suspect’ the driver, and the CIT is far from perfect. This reduces the efficiency of roadside drug testing and makes it difficult to monitor drug-impaired drivers.

The roadside saliva drug testing allows police to test drivers for drugs anywhere, anytime, just as they do with alcohol tests.

Unlike the test for alcohol, however, the result for many of these drugs, including THC, could be return positive, despite the person not being impaired. Unfortunately, there are not yet any quick and easy tests that can accurately test for impairment when it comes to THC. 

What Other Drugs Will Show Up in a Roadside Saliva Drug Test?

According to the Ministry of Transport, saliva testing can detect the use of THC, methamphetamine, benzodiazepines, MDMA, opiates, and cocaine, usually within 30 minutes of ingestion. Medicinal cannabis products containing THC could result in a positive roadside drug test.

Patients using CBD-only medicinal cannabis products should not test positive. However, full-spectrum CBD products may contain small amounts of THC, which could possibly show up on a drug test. 

How Long Does Medicinal Cannabis Stay in My System?

Several factors can affect how long THC stays detectable in your system:

• Saliva tests usually detect THC for approximately 4-6 hours after use but occasionally can be positive for 12 hours or longer.
• THC is not released from the body into saliva, and so it is the residual that remains following use that is being tested. Eating, drinking, brushing teeth and cleaning out the mouth will help decrease this.
• Blood and urine tests can detect THC for much longer periods.

Even if you no longer feel impaired, THC might still be in your system and cause a positive drug test. 

What Does this All Mean for Me?

We understand that this can be stressful, especially for patients who rely on medicinal cannabis to manage their health. Here are some key points to keep in mind:

1. Time Matters: When to Avoid Driving

THC can remain in saliva for several hours after use, even if you feel completely fine. To reduce the risk of testing positive, we recommend:

• Avoiding driving altogether if you feel any impairment
• Follow your doctor’s advice. Generally, we recommend waiting at least 6 hours after inhaling a THC-containing product and at least 10 hours after consuming THC orally before driving

2. Medical Defence: How We Can Support You

If you are prescribed medicinal cannabis and have been using it according to your doctor’s instructions, you may be able to use a medical defence to avoid fines and demerit points. To do this, you need to:

• Have an active prescription
• Follow your doctor’s guidance on how and when to use your medication

We can provide a supporting letter to confirm that your use of medicinal cannabis is legal and prescribed. If you need this documentation, please contact us.

3. Our Practical Tips for Patients:

To stay safe and compliant with the law, here are some practical tips:

• Be mindful of timing: Follow the recommended waiting periods before driving.
• Practice good oral hygiene: If using a full spectrum CBD before driving, brush your teeth and rinse your mouth after taking your medicinal cannabis.
• Keep your medical prescription active: Ensure your script is always up to date to avoid any legal complications.
• Carry your letter from us: If you are ever questioned, having proof of your legal prescription can help.
• Ensure the original pharmacy label is on your medication when traveling with it to confirm its prescribed status.
• Don’t opt for a blood test over salivary testing: Serum THC results could result in more severe penalties.
• Know your rights: If tested, stay calm and follow the process. If you are following medical advice, you are eligible for a medical defence.
• Seek legal support if you receive an infringement notice: Community Law Centres and the Citizens Advice Bureau (CAB) have lists of free lawyers who may be able to assist you.

We’re Here to Support You

At Cannabis Clinic, we are committed to supporting our patients as laws evolve. If you have any concerns about roadside drug testing and how it affects you, reach out to our team.

We’re here to help you navigate these changes and ensure you have the right documentation to protect yourself.