Are magic mushrooms addictive? What research says about dependence and tolerance

People usually ask whether magic mushrooms are addictive because they want to know whether they are “bad for you”. Those are two different questions. A drug can carry a low risk of addiction and still cause serious harm in a single afternoon, and the reverse is also true. This article deals with the first question, addiction and dependence, and points to our other guides for the second.

In short, the sources we opened agree that psilocybin, the main active compound in magic mushrooms, does not behave like drugs with a high risk of compulsive use. Health Canada says “there is little evidence that people can become physically or psychologically dependent on magic mushrooms” (Health Canada). CAMH adds a caution: stopping hallucinogens does not usually cause withdrawal, but people can develop psychological dependence, in which they feel they need the drug (CAMH). Both statements can be true at once, and the rest of this guide explains why.

What does “addictive” mean for a drug like psilocybin?

Researchers split the question into parts. Abuse potential asks whether a drug is rewarding enough that people, or animals, keep taking it. Physical dependence asks whether stopping repeated use causes a withdrawal illness. Tolerance asks whether the same amount has less effect over time. A substance use disorder is a clinical diagnosis: a problematic pattern of use that causes significant impairment or distress.

A 2018 review of psilocybin’s abuse potential explains that addiction science moved, in the 1950s and 1960s, from a focus on physical dependence and withdrawal towards the rewarding effects that drive repeated use, whether or not withdrawal is present (Johnson et al., 2018). That matters here, because a drug with no withdrawal can still be misused. The diagnostic manual used by psychiatrists, the DSM-5, includes hallucinogen use disorders but, according to the same review and a 2022 review, no withdrawal diagnosis for hallucinogens (Johnson et al., 2018; Schlag et al., 2022).

We label the strength of each finding. Established: official Canadian sources and published reviews agree. Limited: an older, small or single study. Preliminary: early or self-selected data. Unresolved: the question has not been answered.

What do animal self-administration studies show?

Self-administration studies are a standard test of abuse potential: animals can press a lever to receive a drug, and researchers watch whether they keep doing so. Drugs with high abuse potential, such as cocaine or opioids, tend to keep animals responding reliably.

Psilocybin does not. In a 2004 study, rhesus monkeys that had already learned to self-administer MDMA were offered several hallucinogens, including psilocybin, DMT and mescaline. No compound produced reliable responding. Some animals did respond in some sessions, but the pattern was sporadic, and the authors suggested these drugs have weak reinforcing effects, or mixed rewarding and unpleasant ones (Fantegrossi et al., 2004). The 2018 review summarises the wider animal evidence the same way: psilocybin, like other classic psychedelics, supports only “marginal, transient” self-administration (Johnson et al., 2018). Evidence: established for the animal findings, which come from several studies.

Animal results are a model, not a verdict on people. The monkeys in the 2004 study had a particular drug history, and they were small groups. The finding fits with what is seen in humans, which is why reviewers give it weight, but on its own it cannot rule out problems in people.

How do abuse-potential reviews rate psilocybin?

The most detailed assessment we found is the 2018 review by Johnson, Griffiths, Hendricks and Henningfield. It works through the eight factors that the US Controlled Substances Act uses to decide how tightly a drug is scheduled, in case a psilocybin medicine is ever approved there. It concludes that psilocybin has some abuse potential, enough to warrant control, but that the evidence does not support placing an approved medicine more restrictively than Schedule IV, the category the authors describe as of intermediate concern (Johnson et al., 2018).

The review gives several reasons. Human studies with a standard questionnaire, the Addiction Research Center Inventory, separated LSD and psilocybin from drugs with a high risk of compulsive use, such as amphetamine, cocaine, opioids and sedatives, and placed them among substances with substantially lower potential for compulsive use and abuse. US treatment-admission data from 2005 to 2015 recorded “hallucinogens”, a category that includes psilocybin with LSD and others, as the main substance in 0.1% of admissions each year. The authors also note that a few lifetime uses is the typical pattern among people who use mushrooms, and that psychological dependence leading to daily use appears rare (Johnson et al., 2018).

Two cautions. This review was written to inform a regulatory process, and its declared interests include research grants from organisations supporting psilocybin research and consulting to groups developing psilocybin as a medicine; the authors state that those organisations had no input into the review. And “low compared with other scheduled drugs” is a relative judgment, not zero. A 2022 review of psychedelic harms reaches the same view, saying psilocybin “does have some limited potential for abuse” while noting that isolated case reports of abuse exist (Schlag et al., 2022). Evidence: established that abuse potential is low relative to most controlled drugs.

Canada and the US schedule drugs under different laws, so the US analysis does not describe Canadian law. For the Canadian position, see are magic mushrooms legal in Canada?

Do you build a tolerance to magic mushrooms?

Yes, and quickly. Health Canada says “it is possible to become tolerant to the drug’s effects with regular use” and that this may occur over several days of continued use (Health Canada). The 2018 review describes tolerance to the psychological and physiological effects of psilocybin as strong (Johnson et al., 2018). CAMH says that with repeated use of hallucinogens the drug can have reduced or no effect, and that sensitivity returns if the person stops for a period of time (CAMH). Evidence: established.

Much of the human evidence is old. A 1961 study at the US Addiction Research Center, by Isbell and colleagues, is titled simply “Cross tolerance between LSD and psilocybin” (Isbell et al., 1961). According to the 2018 review, it gave psilocybin repeatedly to 19 participants for up to 12 days and found diminished effects, and it is one of the studies showing that tolerance to psilocybin carries over to LSD and back (Johnson et al., 2018). The 2022 review says tolerance has been reported to develop rapidly to the psychedelic effects of hallucinogens but not to bodily effects such as pupil dilation, raised blood pressure and faster heart rate (Schlag et al., 2022). The 2018 review describes tolerance to physiological effects of psilocybin as well, so the two reviews do not fully agree on the bodily side. Evidence: established for tolerance and cross-tolerance, though the studies are small and decades old.

Why does this matter for addiction? Reviewers see rapid tolerance as one reason psychedelics are rarely used compulsively: the 2022 review says tolerance develops quickly and “cannot be overcome by dose escalation”, which, together with the lack of withdrawal, points to a low risk of dependence (Schlag et al., 2022). We do not discuss how tolerance changes over time in practice. Taking more to chase an effect that tolerance has blunted is a route to an overwhelming, unpredictable experience, not a way around tolerance. How LSD, psilocybin and DMT compare more broadly is covered in psilocybin, LSD and DMT: the differences.

Is there a magic mushroom withdrawal?

No withdrawal syndrome has been documented. The 2018 review states that no physiological dependence, as shown by withdrawal symptoms, has been documented in humans or animals. In the 1961 study, participants were watched for up to 13 days after psilocybin was stopped and no withdrawal was reported (Johnson et al., 2018). CAMH says stopping hallucinogens “does not usually cause symptoms of withdrawal” (CAMH). Evidence: established.

What is reported is different. CAMH notes that some people feel depressed or anxious long after taking a hallucinogen, and that flashbacks can occur (CAMH). These are after-effects of an experience, not withdrawal from stopping a drug, and they are discussed in our guides to HPPD and short- and long-term effects. If low mood or anxiety continues after any drug use, a health professional is the right person to talk to.

Can people develop problematic use of magic mushrooms?

It is uncommon, but not impossible. A large US population survey, the 2011 to 2012 National Epidemiologic Survey on Alcohol and Related Conditions (36,309 adults), found lifetime hallucinogen use of 9.32%. The authors concluded that hallucinogen use disorder “is relatively uncommon, with a low risk of development following exposure to hallucinogens” (Shalit et al., 2019). The same study found that hallucinogen use was linked with other substance use disorders, personality disorders, PTSD and past suicide attempts. A survey like this cannot say which came first, and it covers hallucinogens as a group, not mushrooms alone. Evidence: established that use disorder is uncommon; preliminary for anything about cause.

The 2022 review adds that very few hallucinogen users report being unable to cut down or control their use, a key sign of dependence, and cites a twin study estimating hallucinogen dependence at 0.2% among women who had used hallucinogens (Schlag et al., 2022). Older estimates were higher, which the review says may reflect counting MDMA and PCP as hallucinogens.

A Dutch government-requested review reached a similar view for mushrooms specifically: the expert panel concluded that the physical and psychological dependence potential of magic mushrooms was low. It also flagged combined use with alcohol, the setting of use, and unpredictable panic attacks and flashbacks as points of concern (van Amsterdam et al., 2011).

Signs that any substance use has become a problem are much the same across drugs: using more often or for longer than intended, failing to cut down, giving up other parts of life, or continuing despite harm. The 2022 review lists criteria of this kind for hallucinogen use disorder (Schlag et al., 2022). If that sounds familiar, the help lines below are a reasonable first step.

Where does psilocybin rank in drug-harm studies?

Several expert panels have tried to rank drugs by overall harm. In the best known, the UK’s Independent Scientific Committee on Drugs scored 20 drugs on 16 criteria of harm to users and to others; alcohol scored highest overall (72), followed by heroin and crack cocaine (Nutt et al., 2010). According to the 2018 review’s summary of that paper’s results, mushrooms received the lowest overall score of all the drugs assessed (Johnson et al., 2018).

A Dutch expert panel ranked 19 recreational drugs on acute and chronic toxicity, addictive potency and social harm (van Amsterdam et al., 2010); the 2018 review reports that it rated psilocybin mushrooms the least harmful drug examined, both to the individual and to the population. The same review says a survey of experienced drug users gave mushrooms the lowest harm ratings too (Johnson et al., 2018).

These rankings are structured expert or user judgments, not measurements of harm in a population, and they score typical use, not the worst case. A low ranking says mushrooms cause less total harm than alcohol or heroin across a society. It does not say that a particular person, on a particular day, will come to no harm. Evidence: established that rankings place mushrooms low; limited as a guide to individual risk.

Are magic mushrooms bad for you if they are not addictive?

They can be. Low addiction potential describes one kind of risk. Health Canada lists anxiety, panic, paranoia and confusion among short-term effects, warns that people with psychiatric or heart conditions may face higher risk, and says that using mushrooms with cannabis, amphetamines, alcohol and other substances “elevates the risks of serious side effects and adverse events”. It also states that no studies have evaluated the long-term effects of repetitive use of magic mushrooms (Health Canada).

The 2018 review names the potential harms as dangerous behaviour in unprepared, unsupervised users and worsening of mental illness in people with or predisposed to psychotic disorders (Johnson et al., 2018). Mistaking a poisonous mushroom for a magic one is a separate danger that has nothing to do with addiction. For the full picture, read:

• Are magic mushrooms safe? for psychological, physical and poisoning risks, graded by evidence.
• Can magic mushrooms cause psychosis? for who is at higher risk.
• Magic mushrooms and antidepressants for what is known about medication interactions.
• How to help someone having a bad trip for what official sources say to do in a crisis.
• How long do shrooms stay in your system? for testing questions.

Some trials are testing psilocybin as a treatment for addiction to other drugs. That research is separate from the question of whether mushrooms themselves are addictive, and it uses screened volunteers in supervised settings. We cover it in psilocybin for alcohol use disorder.

Where can you get help with substance use in Canada?

These services were listed on the official pages we opened on 17 October 2026. They are information and support lines, not emergency services. In an emergency, call 911.

• Suicide crisis: call or text 9-8-8, the Suicide Crisis Helpline, 24 hours a day, every day of the year. The site says to call 9-1-1 right away if your safety is at risk.
• Ontario: ConnexOntario offers free 24/7 access to mental health, addiction and problem gambling information at 1-866-531-2600, or text CONNEX to 247247. The Government of Canada’s substance-use help page also lists it (Government of Canada).
• Young people: Kids Help Phone, 1-800-668-6868 or text 686868, 24/7, as listed on the same federal page and on CAMH’s hallucinogens page (Government of Canada; CAMH).
• Indigenous people across Canada: the Hope for Wellness Help Line, 1-855-242-3310, 24 hours a day, 7 days a week, in English, French, Cree, Ojibway or Inuktitut (Government of Canada).
• Other provinces and territories: the federal substance-use help page lists local lines. In Toronto, CAMH says its Access CAMH intake line is 416-535-8501, option 2, and that people can self-refer to its addiction services (CAMH).

What is still not known?

• Rates of problematic use of mushrooms alone. Most survey data group psilocybin with LSD and other hallucinogens.
• Canadian figures. We found no Canadian study of dependence on magic mushrooms, so we give none.
• Long-term effects of repeated use. Health Canada says no studies have evaluated them.
• Whether today’s patterns of use, including frequent small amounts, change the picture. The human tolerance studies are from the 1960s and involved few people. For what controlled trials of microdosing do and do not show, see microdosing psilocybin.
• Why some people do develop a problem. The survey links between hallucinogen use and other disorders cannot show cause.

Shroomverse sells mushroom products. This article is general information about what official sources and research say about addiction, dependence and tolerance. It is not medical, legal or purchasing advice, and it does not encourage anyone to use drugs.