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Doctor's Assessment Included

Every result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.

Drug Screening

Cannabinoids (THC)

A cannabinoids/THC urine test is a qualitative screening that detects the presence of THC metabolites in urine. THC (delta-9-tetrahydrocannabinol) is the primary psychoactive compound in cannabis.

What It Measures

This test detects the presence of THC-COOH (11-nor-9-carboxy-THC), the primary urinary metabolite of THC. After cannabis use, THC is metabolised in the liver and its metabolites are excreted in urine over an extended period. The test provides a qualitative result indicating whether THC metabolites are present above the assay cut-off level.

THC metabolites are lipophilic and accumulate in fatty tissue, which contributes to the potentially long detection window, particularly with regular use.

Why It Matters

THC testing is one of the most commonly performed drug screenings and is a standard component of workplace, clinical, and forensic drug testing panels. Detection indicates cannabis exposure within the relevant detection window.

Interpretation should consider frequency of use, as single-use and chronic use produce very different detection windows. Clinical context is important for appropriate assessment of results.

When to Test

Testing may be relevant as part of standard workplace drug screening, pre-employment testing, clinical assessments, substance abuse treatment monitoring, or legal and forensic evaluations.

Consult a healthcare professional for guidance on interpretation, particularly given the wide variation in detection windows based on usage patterns.

Frequently Asked Questions

How long can THC be detected in urine?
The detection window for THC in urine varies significantly. For occasional users, THC metabolites may be detectable for approximately 3 to 5 days. For regular or heavy users, detection may extend to 30 days or more due to accumulation in fatty tissue.
Can passive cannabis exposure cause a positive result?
Passive exposure to cannabis smoke is unlikely to produce a positive result at standard cut-off levels used in workplace screening. However, prolonged exposure in an enclosed environment may in rare cases lead to detectable levels. Confirmatory testing can provide additional clarity.
What should I expect from a THC urine test?
The test requires a urine sample, which is screened for THC metabolites using immunoassay. Results are qualitative, indicating detection above or below the assay threshold. Confirmatory testing using mass spectrometry may be performed following a positive screening.