Mouth Swab vs Urine Test for Cannabis: Which is More Accurate?
Discover the differences between mouth swab and urine tests for cannabis detection, and choose the right option for your needs.
A cannabis drug test looks for THC and the metabolites your body creates after you consume it, and how long those markers stay detectable depends on the test type, how often you use, and your own biology. This guide answers the questions US shoppers ask most before buying an at-home kit or planning around an employer screen.
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Most workplace screens start with a rapid immunoassay, which compares your sample against a fixed cutoff concentration. Urine screening commonly uses a 50 ng/mL threshold for THC metabolites, with any presumptive positive sent for a more specific confirmation method such as GC-MS at a lower cutoff. Oral fluid screens generally use tighter thresholds because saliva reflects recent use, while hair testing measures metabolites trapped in the hair shaft over a much longer window and blood testing captures only very recent exposure. At-home strips work on the same immunoassay principle, so a faint second line still counts as a negative result. Always check the expiration date and follow the timing instructions on the package.
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Orders ship in plain, discreet packaging with no branding on the outside, and most in-stock items leave the warehouse within one business day. Tracking is emailed as soon as your label is created. Unopened test kits can be returned within 30 days for a refund, and if a kit arrives damaged or past its expiration date, contact support for a replacement at no cost.
Cannabis Drug Test Cutoff Levels Guide
Occasional users often clear urine screens in a few days, while heavy daily users can test positive for weeks or longer. Hair tests can reach back roughly 90 days.
In enclosed, poorly ventilated spaces with heavy smoke, trace exposure has occasionally produced weak positives on sensitive screens, though this is uncommon in normal settings.
There is no strong clinical evidence that commercial detox products reliably clear THC metabolites. Hydration and time are the factors most consistently linked to lower concentrations.