Saliva testNew Zealand
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220. Saliva test
A saliva test is a roadside screening test used to detect recent use of certain drugs that can affect driving ability. A sample of saliva is collected from the mouth and tested with a portable device for specified substances. The test is generally used as an initial screening rather than as the final evidential analysis. If the result is positive, a more precise saliva analysis or, in some circumstances, a blood test may follow.
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What is a saliva test?
A saliva test is a screening test that uses oral fluid to detect the recent presence of certain drugs or their metabolites.
How is a roadside saliva test performed?
A sample of saliva is collected from inside the mouth and tested using an approved portable device. The exact procedure and substances tested depend on the country.
Is a saliva test the same as a saliva analysis?
No. A saliva test is generally a preliminary roadside screening, while a saliva analysis is a laboratory examination used to confirm and measure specified substances more precisely.
What happens after a positive saliva test?
Depending on local law, a positive result can lead to a saliva analysis, blood test, temporary driving prohibition or further legal proceedings.
Can a saliva test detect every drug?
No. Saliva tests are designed to detect specific substances. The drugs included and the detection thresholds depend on the testing device and applicable law.
Can you refuse a saliva test?
Rules vary between countries, but refusing a legally required saliva test can itself lead to penalties or an immediate restriction on driving.

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New Zealand