How long do shrooms stay in your system? Drug tests in Canada

People who search “how long do shrooms stay in your system” are usually asking two things. How long does the body keep the active compound? And would anyone find it if they looked? Research answers the first only in part, and the second depends on who is testing, with what, and why.

This guide sticks to peer-reviewed pharmacology, Government of Canada sources and the Ontario Human Rights Commission. It does not explain how to pass or avoid a test, and nothing in it is a safe-to-drive or safe-to-work timeline.

How long does psilocin stay in the body, according to research?

Psilocybin is the compound mushrooms store. The body quickly turns it into psilocin, the form that acts on the brain. In a 1997 study of six volunteers, plasma psilocin peaked within minutes of an intravenous psilocybin dose, which the authors took as a sign of rapid dephosphorylation (removal of a phosphate group) (Hasler et al., 1997). After an oral dose, plasma psilocin peaked about 105 minutes later, on average, in the same study.

A 2017 study found no psilocybin itself in the plasma or urine of its 12 volunteers, only psilocin and its breakdown products (Brown et al., 2017). That is why the research, and any test aimed at mushrooms, focuses on psilocin rather than psilocybin.

What is psilocin’s half-life?

A half-life is the time it takes for the concentration in blood to fall by half. In Brown and colleagues’ study the mean elimination half-life of psilocin was 3 hours (standard deviation 1.1). The authors also saw a longer tail of elimination in some people, which they suggest reflects psilocin being released again from its glucuronide, a conjugated form the body makes for excretion (Brown et al., 2017).

A 2025 systematic review of 14 studies, six of them clinical studies with 112 healthy participants, reports elimination half-lives ranging from 1.5 to 4 hours across studies, and says pharmacokinetics varied with dose, route and species (Meshkat et al., 2025). A half-life is not a countdown to zero. It describes how fast a concentration falls, not the point at which a test can no longer find it.

How long can psilocin be found in urine?

The best-known urine study followed eight volunteers who received psilocybin by mouth and collected all urine for 24 hours. Free psilocin in urine peaked at up to 870 µg/L in the 2 to 4 hour collection. The lab method’s limit of quantitation, the lowest level it could measure reliably, was 10 µg/L, and it was usually reached 24 hours after the dose. Over those 24 hours, 3.4% of the dose appeared as free psilocin (Hasler et al., 2002).

That was not the whole picture. When the researchers added an enzyme (beta-glucuronidase) to the urine, measured psilocin roughly doubled, which showed that part of it is excreted attached to glucuronic acid. They concluded that this step extends the time psilocin can be detected in urine (Hasler et al., 2002). The 2017 study fits the same picture: less than 2% of psilocin’s total clearance was renal clearance of intact psilocin, so most leaves the body in other forms (Brown et al., 2017). The 2025 review lists the liver enzymes CYP2D6 and CYP3A4, and monoamine oxidase A, among those that break psilocin down (Meshkat et al., 2025).

What these studies cannot tell you

• They stop at 24 hours. The urine and blood collections in the studies above ran for 24 hours (Hasler et al., 2002; Brown et al., 2017), so they say nothing about later times.
• Detection depends on the method. A result is “found” or “not found” relative to a test’s cutoff. A lab with a different cutoff or technique would be expected to give a different answer.
• They gave volunteers psilocybin itself. Mushrooms are a different thing to test, and we did not find a study that followed psilocin in urine after mushroom ingestion.
• The groups were small and healthy. The 2017 authors note variation in psilocin clearance between people that body weight did not explain (Brown et al., 2017).
• They measured drug concentrations, not effects, ability to work or fitness to drive.

For how long the effects themselves last, see our guide on how long magic mushrooms last. Detection and effects are different questions.

Do standard drug tests look for psilocybin?

A test finds only what it is built to look for. The clearest published example of a “standard” panel we could find is the US federal urine panel, which the US Department of Health and Human Services (HHS) reissued in March 2026 with no change to its analytes. It lists a marijuana metabolite, a cocaine metabolite, opioids (codeine, morphine, hydrocodone, hydromorphone, oxycodone, oxymorphone and 6-acetylmorphine), phencyclidine, fentanyl and norfentanyl, amphetamines and MDMA/MDA. Psilocybin and psilocin are not on it (HHS testing panels notice, Federal Register, 13 March 2026). Under the underlying guidelines, federal agencies must test for marijuana and cocaine metabolites and may test for the other drugs on the panel (HHS Mandatory Guidelines, Federal Register, 2023).

Two cautions. First, this is a United States federal programme for its own workforce, not a Canadian standard. We found no Canadian government body that publishes a standard workplace panel, and we could not verify the test menu of any Canadian lab, so what a private employer or lab includes is a matter for that employer’s policy and that lab. Second, HHS publishes the panel in a separate notice each year, so the list can change (Federal Register, 2023; 2026).

“Not on the standard panel” is not “cannot be detected.” The research above measured psilocin with specialised chromatography methods, including liquid chromatography with tandem mass spectrometry (Brown et al., 2017). A tester who wants to look for it can.

Can an Ontario employer drug test you?

It depends on the job and the circumstances. The Ontario Human Rights Commission (OHRC) sets out its position in its Policy on drug and alcohol testing, revised in 2016. The policy is built around the Ontario Human Rights Code, which treats addictions as disabilities. It is the Commission’s position rather than a statute, and individual cases turn on their facts. In summary:

• Pre-employment. The OHRC takes the position that testing as part of initial applicant screening is prohibited under subsection 23(2) of the Code. It notes that the case law has not ruled out testing after a conditional job offer for a safety-sensitive position, but recommends against it (OHRC, 2016).
• Random testing. The OHRC says research has not confirmed a drug test that works like a breathalyzer for alcohol, in measuring current impairment accurately, with little intrusion and fast results. Random testing might be justified only for safety-sensitive positions, and only when specific conditions are met (OHRC, 2016).
• Reasonable grounds and post-incident. Testing may be acceptable in specific circumstances where there is a link between impairment and safety-sensitive duties, and “reasonable grounds” should rest on objective evidence such as specific observed behaviours (OHRC, 2016).
• What a urine test shows. The policy says urinalysis can detect past use but not how much was used or whether the person is currently impaired (OHRC, 2016).
• Consequences. The OHRC raises concerns where a positive test leads to automatic discipline, and says policies should not treat any substance use as if it were an addiction (OHRC, 2016).

The OHRC also says the Code protects casual or recreational users only if they are perceived to have an addiction (OHRC, 2016). In plain terms, the Code’s protection centres on addiction and perceived addiction, not on use as such. Collective agreements, privacy law and workplace safety rules can matter too. This page is not employment advice: for a specific situation, speak to a union representative or a lawyer.

What about federally regulated employers?

Federally regulated employers fall under the Canadian Human Rights Act instead. The Canadian Human Rights Commission’s 2017 guide, Impaired at Work, says testing someone who does not hold a safety-sensitive position is rarely permissible, that testing is a form of medical examination with privacy and human rights implications, and that a positive drug test shows traces of a drug but cannot prove the person is impaired at the time of the test. It also says an employer who receives a positive result has an obligation to start a conversation about possible substance dependence (CHRC, 2017).

That guide is now listed in the Commission’s archive as kept for reference and not updated since it was archived (CHRC archive page). It also warns that it may contain outdated information on human rights legislation. As of 4 October 2026 we found no replacement guide, so check the Commission’s website for its current position. The guide also says employers may have policies on substance use during working hours, and that employers in some regulated safety-sensitive industries may be able to have policies on off-duty use (CHRC, 2017).

What does Canada’s impaired-driving law say about psilocybin?

This is the part where the research numbers matter least and the law matters most. Under section 320.14 of the Criminal Code, it is an offence to operate a conveyance while your ability to do so is impaired to any degree by alcohol or a drug. “Operate” covers driving a motor vehicle and also having care or control of it (Criminal Code, s. 320.14; s. 320.11).

A separate offence turns on blood concentration. Within two hours after ceasing to operate a conveyance, having a blood drug concentration at or above the level prescribed by regulation is an offence (Criminal Code, s. 320.14). The Blood Drug Concentration Regulations prescribe “any detectable level” for psilocybin and for psilocin. They set the same “any detectable level” standard for LSD, PCP, ketamine, cocaine, methamphetamine and 6-monoacetylmorphine, while THC and GHB have numeric limits (Blood Drug Concentration Regulations, s. 2). The Regulations are current to 21 September 2026 and were last amended in 2018.

The studies above measured psilocin in plasma and urine for 24 hours after a dose (Hasler et al., 2002; Brown et al., 2017). None of the sources we read ties a blood level of psilocin to driving ability, and the regulation is a legal line, not a pharmacology finding. We did not review the evidence behind it. For the same reason, we cannot offer any time after which driving is safe or lawful, and nothing here should be read that way.

How does roadside testing work for drugs in Canada?

If a peace officer has reasonable grounds to suspect a person has a drug in their body and has operated a conveyance within the preceding three hours, the officer can demand physical coordination tests and an oral fluid sample for approved drug screening equipment (Criminal Code, s. 320.27). The Order currently lists two approved devices, the Dräger DrugTest 5000 and the Abbott SoToxa (Approved Drug Screening Equipment Order).

The Government of Canada’s regulatory statements describe what those devices look for. The Dräger test checks oral fluid for THC and cocaine (Canada Gazette, 2018), and the SoToxa checks for THC. They add that screening equipment must detect one or more of THC, cocaine and methamphetamine to be approved (Canada Gazette, 2019). So the approved roadside oral fluid screeners are not designed around psilocin.

That does not end the process. If an officer has reasonable grounds to believe a person drove while impaired by a drug, the officer can demand an evaluation by an evaluating officer, blood samples, or both. If that evaluation gives the evaluating officer reasonable grounds to believe a drug type is impairing the person, the type list includes hallucinogens, and the officer can demand an oral fluid, urine or blood sample (Criminal Code, s. 320.28). Failing or refusing to comply with these demands without reasonable excuse is a separate offence (Criminal Code, s. 320.15).

We have not covered penalties, provincial licence consequences or how courts have applied these provisions. Those are separate questions, and a lawyer is the right person to ask about a specific case. Our guide to penalties for psilocybin in Canada covers the wider legal picture.

What we still don’t know

• How long psilocin or its conjugates can be found with the most sensitive methods. The studies we read stop at 24 hours.
• How results differ after eating mushrooms, whose content varies, compared with a measured dose of psilocybin.
• Which panels Canadian employers and labs actually use. We found no published standard.
• Whether the Canadian Human Rights Commission will publish a replacement for its archived 2017 guide. We found none as of 4 October 2026.
• How police and courts apply the “any detectable level” blood limit in practice. We did not review case law.
• Rules in other settings, such as sport, probation, custody, travel and immigration. We did not research them.

If you are worried about a specific test, a specific job or a driving charge, this page cannot answer it. Ask an employment or criminal lawyer, or a union representative. If you or someone else needs urgent medical help, call 911; for a possible poisoning call the Ontario Poison Centre on 1-800-268-9017; for a crisis call or text 9-8-8. For questions about legality, see are magic mushrooms legal in Canada. For background on the compound, see what is psilocybin.

Shroomverse sells mushroom products. This article is general information about drug testing, pharmacology and the law. It is not medical, legal, employment or purchasing advice, and it does not encourage anyone to use drugs.