THC urine test: how long does THC stay detectable?
By the Golden High teamUpdated 18 October 20269 min read
Drug testing
THC urine test: how long you stay positive mostly depends on how often you use. A THC urine test is usually positive for about 3 days after a one-off use, one to two weeks with daily use, and sometimes more than 30 days in a heavy user. It doesn't look for THC itself but for its metabolite, THC-COOH, which your body clears slowly. Here are the detection times reported by medical sources, the cut-offs labs use, what happens with CBD and novel cannabinoids, and the real false positives.
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THC urine test: it looks for a waste product, not THC.
When you use cannabis, your liver breaks THC down into several metabolites. The main one, THC-COOH (11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid), has no psychoactive effect but ends up in your urine. That's what the test targets. It's also why a urine test tells you that someone used cannabis at some point, without telling you whether they're high at the time the sample is taken.
THC is highly fat-soluble. In a regular user, it builds up in fat tissue and is then released slowly: that's what explains the long detection windows, as the Mayo Clinic Proceedings review on interpreting urine drug tests points out.
A strip that reacts is only a preliminary result: only lab confirmation identifies the exact molecule.
Detection times
THC urine test: how long until you test negative.
It's the question people ask most. The honest answer: it depends mainly on how often you use, then on the dose, the THC content, your body fat, your metabolism and how hydrated you are. The two references below give you ballpark figures, not guarantees.
| Usage profile | Mayo Clinic Proceedings (2017) | Drogues Info Service (2025) |
|---|---|---|
| Single use | About 3 days | 3 to 5 days (occasional use) |
| Moderate use (about 4 times a week) | 5 to 7 days | — |
| Daily use | 10 to 15 days | 30 to 70 days (regular use) |
| Heavy chronic user | More than 30 days | — |
The gaps between the two tables aren't a mistake: they reflect how much people differ and how hard it is to define “regular use”. Drogues Info Service, the French public drug information service, is clear about it: these times are only rough guides, and there's no way to know precisely how long you personally will test positive.
- Urine: the longest window, from a few days to several weeks.
- Saliva: 6 to 8 hours for occasional use, up to 24 hours for regular use, and up to 8 days for heavy use, according to Drogues Info Service.
- Blood: THC itself for 2 to 8 hours after occasional use, its metabolite for up to 72 hours.
Roadside testing in France uses saliva. We cover it in detail in our article on the THC, HHC and CBD saliva test.
What the sources say
What the key studies show.
Several studies answer the questions that keep coming up: CBD, passive exposure, new cannabinoids. All the references are at the bottom of the page.
Mayo Clinic Proceedings · 2017
Review on interpreting urine drug tests: about 3 days after a single use in a non-user, more than 30 days in a chronic user. Federal cut-offs: 50 ng/mL for screening, 15 ng/mL for confirmation.
Journal of Analytical Toxicology · 2020
Six adults received 100 mg of pure CBD, oral or vaporised: out of 218 urine samples, only one reacted on screening at 20 ng/mL, and none was confirmed. With a CBD-rich flower containing 3.7 mg of THC, two samples went over the 50 ng/mL cut-off.
Passive exposure · study cited by the Mayo Clinic
Non-smokers spent an hour with smokers: no positives at 20 ng/mL in a ventilated room. In a closed room, with cannabis at 11.3 % THC, several positives at 20 ng/mL and just one at 50 ng/mL.
Forensic Toxicology · 2025
HHC metabolites (HHC-COOH) react with three commercial THC urine tests. The authors urge caution about false positives caused by HHC.
What this means in practice: pure CBD hardly ever triggers the tests, but a product that contains traces of THC can trigger one, especially with heavy, repeated use. And novel cannabinoids aren't “invisible”.
CBD and novel cannabinoids
CBD and urine tests: no guarantee.
In France, hemp products are allowed as long as they contain less than 0.3 % THC. Less than 0.3 % isn't zero: smoking a lot of a product that contains traces of THC means building up a little of it. The studies above show it's rarely enough to cross the cut-off, but it can happen.
Pure CBD (isolate)
No THC, so very little risk. Provided the label is telling the truth: the ANSM (the French medicines agency) reports products sold as CBD that actually contained too much THC or synthetic cannabinoids.
Hemp flowers and resins
Possible traces of THC below 0.3 %. Heavy daily use increases the risk of a reaction on screening.
HHC and derivatives
Classed as controlled drugs in France since 13 June 2023 (ANSM decision). According to a 2025 study, their metabolites react with THC urine tests.
Delta-P (Golden High)
A CBDX-based range, below 0.3 % THC and lab-tested. No published study tells us how it behaves on a test, so we don't promise any result.
To understand what “THC-free” really means on a label, read can you trust THC-free CBD products. How Delta-P works is explained on our dedicated page.
False positives
False positives exist, but they're rare.
The first test, the immunoassay, picks up a molecular shape rather than one specific molecule. So some substances can trigger it. The Mayo Clinic Proceedings lists several for cannabinoids.
- Efavirenz, an antiretroviral drug: a well-documented interference, caused by one of its metabolites.
- Anti-inflammatories (NSAIDs) such as ibuprofen or naproxen: very rare, 2 false positives out of 510 samples in the study cited.
- Proton pump inhibitors: a single reported case with pantoprazole, plus a mention in its package leaflet.
- Dronabinol, a medicine based on synthetic THC: it gives a true positive, impossible to tell apart from cannabis.
- Some baby toiletries: reactions seen at 20 ng/mL in newborns, never at the 50 ng/mL cut-off.
If you're taking medication, mention it before the sample is taken. And if a screening comes back positive when you haven't used anything, ask for lab confirmation by chromatography: that's the result that counts.
The rules in France
Who can make you take a urine test in France.
In France, lab urine drug tests are mainly used in a medical, legal or occupational health setting. On the road, it's saliva that gets sampled, with lab confirmation.
At work
According to the INRS (the French occupational health and safety institute), a urine test is a medical biology test: it can only be carried out by a medical biologist or under their responsibility. An employer can't force the occupational doctor to prescribe one.
Saliva test
Under certain conditions (company rules, safety-critical jobs, the right to a second opinion), a French employer can have a saliva test carried out. That's the framework set by the Conseil d'État (France's highest administrative court) in December 2016, and restated by the INRS.
On the road
Saliva screening. We've explained what happens with CBD in smoking CBD before driving.
Medical follow-up
In medical or addiction care, it's the doctor who prescribes the test, and the result is covered by medical confidentiality.
Key takeaways
No miracle trick, just time.
The internet is full of “methods” to pass a test. We won't pass any of them on: at best they don't work, at worst they're dangerous, and labs check sample integrity, as the Mayo Clinic Proceedings review describes. The only thing that brings THC-COOH down is time without using.
Plan ahead
If you know a test might come up (work, medical follow-up, driving licence), the safest option is not to use anything at all, hemp included.
Be upfront
Mention any medication and, if you use CBD, tell the doctor: they'll be able to interpret the result better.
Insist on confirmation
A positive screening without lab confirmation is only a preliminary result. Ask for the confirmation analysis.
If you choose to use, do it with products whose strength is stated and lab-tested, like our Delta-P flowers, starting with the Amnesia Delta-P 12 %. Adults only, never before driving.
Your questions
What people ask us about urine tests.
THC urine test: how long until you test negative?
About 3 days after a single use according to the Mayo Clinic Proceedings (3 to 5 days according to Drogues Info Service), 10 to 15 days with daily use, and sometimes more than 30 days in a heavy user. There's no way to know your exact window.
How long does a joint stay in your urine?
For a single joint in someone who doesn't usually smoke, detection generally lasts around 3 days. The more often you use, the longer the window gets.
Does CBD show up on a urine test?
The test doesn't look for CBD but for a THC metabolite. Pure CBD hardly ever triggers it. On the other hand, a hemp product that contains traces of THC can give a positive result with heavy use.
What is the cut-off for a THC urine test?
In the United States, the federal cut-off is 50 ng/mL for screening (some labs use 20 ng/mL) and 15 ng/mL of THC-COOH for lab confirmation.
Can you test positive for THC from other people's smoke?
It's rare. In a ventilated room, no non-smoker tested positive in the study cited. In a closed room with very strong cannabis, only one went over the 50 ng/mL cut-off.
Can a medication cause a false positive for cannabis?
Yes, rarely: efavirenz is the best-documented case, anti-inflammatories and pantoprazole far more exceptionally. Lab confirmation settles the question.
Does HHC show up on a urine test?
Its metabolites can trigger THC urine tests, according to a study published in 2025. And HHC has been classed as a controlled drug in France since 13 June 2023.
Sources
The references cited in this article.
- Mayo Clinic Proceedings (2017). Clinical Interpretation of Urine Drug Tests: What Clinicians Need to Know About Urine Drug Screens.
- Drogues Info Service (2025). Table of detection times (in French).
- Journal of Analytical Toxicology (2020). Urinary Pharmacokinetic Profile of Cannabinoids Following Administration of Vaporized and Oral Cannabidiol and Vaporized CBD-Dominant Cannabis.
- Forensic Toxicology (2025). Cross-reactivity of the epimers of 11-nor-9-carboxy-hexahydrocannabinol, metabolites of hexahydrocannabinol, with panel tests for urinary Δ9-tetrahydrocannabinol metabolites.
- INRS. Addictions: regulations (in French).
- ANSM (2025). Rise in poisonings caused by CBD-based products containing other substances (in French).
- ANSM (2023). ANSM classifies hexahydrocannabinol (HHC) and two of its derivatives as controlled drugs (in French).
