Magic Mushrooms: Risks and Side Effects

Magic mushrooms are often viewed as a path to insight or personal exploration, but they also come with physical, psychological, and legal risks. Research suggests psilocybin can produce both meaningful and challenging effects depending on mindset, environment, dose, and drug interactions.¹

This guide outlines the short-term and long-term side effects of psilocybin, potential risks, who may be more vulnerable to harm, and what practical harm reduction strategies are recommended by researchers and public health sources.

Understanding Magic Mushrooms and Psilocybin

“Magic mushrooms” are fungi that contain psilocybin, a compound the body converts into psilocin. Psilocin primarily acts on serotonin 5-HT2A receptors, influencing sensory processing and the perception of time, space, and self.¹ For more background on what magic mushrooms are and how they work, see our dedicated guide.

Magic mushrooms, like other hallucinogens, are capable of producing intense “trips” when consumed in higher doses. However, even small quantities are able to cause shifts in mood and trigger visual and auditory hallucinations.

For an overview of psilocybin versus other hallucinogens, see our comparison guide.

Clinical vs Recreational Context

Psilocybin mushrooms have captured the interest of scientists and medical professionals because of their unique effects on the brain. Ongoing studies continue to assess their impact on cognition and a host of mental health disorders. These research efforts employ screening, dose control, medical oversight, and therapeutic frameworks to achieve repeatable and consistent results.

However, most magic mushroom use occurs outside of the lab. Here, psychonauts essentially experiment with different strains and doses to induce the desired effects. The bulk of recreational use revolves around individuals seeking to experience an altered state of consciousness, whether for spiritual reasons or simply to explore what these fascinating fungi have to offer.

Because recreational use involves more variability in dose, purity, drug interactions, and environment, the outcomes are much less predictable than in a research setting.²

Short-Term Physical and Psychological Effects

Magic mushrooms can cause both short- and long-term effects. Before we examine their potential long-term impact, let’s consider their short-term physical and psychological effects.

Physical Effects

After consuming magic mushrooms, many users experience acute physical effects that include:

• Nausea
• Vomiting
• Elevated heart rate
• Increased blood pressure
• Dilated pupils are regularly noted

Dizziness, headaches, or muscle fatigue may also occur.^{1 2}

Psychological Effects

As one of the most powerful known hallucinogens, psilocybin causes intense emotional states that can rapidly shift from positive to negative. These contrasting sensations include:

• Euphoria
• Fear
• Panic
• Confusion

Visual distortions, sound amplification, and altered time perception are also common experiences. “Bad trips”, marked by intense fear or overwhelming distress, are more likely with higher doses or stressful surroundings.^{1 2}

For practical strategies on how to prevent a bad psychedelic trip, see our harm reduction guide.

Long-Term and Latent Side Effects

Long-term issues are uncommon, but not impossible. Vulnerability, dose, frequency, and mental health history matter. Before taking magic mushrooms, it’s paramount to familiarise yourself with the potential long-term mental health risks.

Mental Health Risks

Not everyone reacts to psilocybin the same way, especially when it comes to mental health. Most people don’t experience long-term psychiatric issues, but this is one of the most important risk categories to take seriously.

Case reports describe episodes of psychosis or mania, particularly in people with personal or family histories of bipolar disorder, schizophrenia, or other conditions where brain chemistry is already more vulnerable.³ These reactions tend to happen more often at higher doses, chaotic settings, or with repeated use without guidance.

There are also examples of mood dips or depressogenic relapse after consistent, unsupervised use, especially when someone is using mushrooms frequently as “self-medication” rather than occasional exploration.⁹

In simple terms, psilocybin can amplify what’s already there, good or bad. If someone is predisposed to instability, these risks become significantly greater. This is why screening, support, and a stable mental baseline before using psychedelics is considered vital in clinical approaches.

Flashbacks and HPPD

Flashbacks can occur unexpectedly for some people, sometimes weeks after the experience, even when the original trip felt positive or uneventful. Studies suggest that around 8–9% report these brief, spontaneous after-effects.⁴ These are usually short-lived, but for a small minority, they can feel unsettling.

A far rarer condition, called Hallucinogen Persisting Perception Disorder (HPPD), involves ongoing visual disturbances, such as halos, tracers, or “visual snow”.⁵ Most people will never experience this, but it’s an important reminder that long-lasting perceptual changes are possible, particularly with higher frequency use, stressful contexts, or polydrug combinations.

Contextual and Social Risks

Where, how, and with whom mushrooms are used influences risk as much as dose. If you are picking mushrooms outside, our overview on how to identify magic mushrooms in the wild can help reduce misidentification. For people cultivating their own supply, a guide on how to harvest magic mushrooms properly can help reduce contamination or dosing uncertainty.

Risky Behaviour During Trips

During intense psychedelic experiences, judgment and coordination can shift very quickly. This is where the greatest real-world harm often shows up, not from the compound itself, but from what happens while someone is intoxicated. Poor spatial awareness, confusion, sensory distortion, and slowed reaction time can lead to falls, wandering into traffic, risky decisions, or becoming lost in unfamiliar places.

Smoking mushrooms is also strongly discouraged. Psilocybin and psilocin break down under high heat, rendering them ineffective, and inhaling burnt fungal material may irritate or harm the lungs.^{10 11}

Polydrug Use and Interactions

Mixing psilocybin with other substances is one of the fastest ways to make effects unpredictable. SSRIs or SNRIs may diminish, distort, or alter the experience of psilocybin. Some people report almost nothing, others report uncomfortable emotional spikes.^{7 8}

MAOIs are a serious red flag. Combining them with psilocybin can raise the risk of serotonin toxicity. Avoid this pairing entirely.⁶

Alcohol, cannabis, or stimulants can also layer confusion, anxiety, or agitation on top of an already altered state. For harm reduction, psilocybin is safest when used alone, in a calm environment, with no other substances in the system.

Legal Status

Psilocybin remains illegal or heavily controlled in most parts of the world. Exact penalties vary depending on your location. Some places treat possession as a serious criminal offence, while others have shifted toward decriminalisation or lower enforcement priority.

Even in regions where penalties have relaxed, that doesn’t mean open public use is safe or consequence-free. Public intoxication, unsafe environments, impaired judgment, or police interaction can still lead to legal, medical, or social problems. Use settings, laws, and risks are always context-dependent, and keeping updated with local regulations matters just as much as understanding the substance itself.

Microdosing Risks

Microdosing refers to taking very small, sub-perceptual amounts of psilocybin on a repeated schedule rather than having full “trip-level” experiences.

Although it has gained popularity online, the evidence supporting it remains shaky. Controlled clinical studies often show microdosing results aren’t that different from placebo, meaning a lot of the reported benefits may simply come from expectation, mindset, or belief rather than pharmacological effect.¹²

Some people also report subtle downsides: increased anxiety, poor sleep, irritability, or feeling mentally “scattered” rather than sharper. Long-term safety data is extremely limited, and because microdosing involves repeated exposure over long windows, small risks may compound over time. This makes a cautious, slow, self-aware approach especially important, or choosing not to microdose at all if uncertain.

Who Should Avoid Magic Mushrooms?

Some people carry a much higher risk from psilocybin use. For these groups, avoiding use entirely is the more responsible option, even at low doses, because reactions can be harder to predict and more difficult to manage if something goes wrong. These groups include:

• People with personal or family history of bipolar disorder, psychosis, or schizophrenia³
• Anyone taking psychiatric medication (SSRIs, SNRIs, MAOIs, antipsychotics)
• Adolescents and young adults, due to ongoing brain development
• Pregnant or breastfeeding people (safety data remains insufficient)¹
• Anyone who doesn’t have a safe, stable setting or support present

Tips for Reducing Risk

If someone chooses to use psilocybin, small practical steps can make the experience more manageable and less volatile. Our guide on how to take magic mushrooms safely explains dosing, preparation, and setting in more depth.

Our guide on how to prepare for a psychedelic trip covers mindset, environment, and planning before a session.

• Choose a calm, familiar environment where you feel safe
• Have a trusted sober sitter present throughout the experience
• Start with a very small dose and wait several hours before considering more
• Avoid mixing with alcohol, stimulants, or serotonergic drugs⁶
• Stay hydrated, rest when needed, and eat lightly beforehand
• Take time to reflect afterwards; journaling and integration can help process and make sense of the experience
• Know who you would call or where you would go if panic or confusion escalates beyond what you can manage on your own

Navigating Psychedelic Experiences Safely

Magic mushroom experiences can be meaningful, confusing, uplifting, or confronting, sometimes all in the same session. While most people return to baseline without lasting harm, there is still room for unpredictability, particularly when dose, set, setting, or product quality is uncertain.

If someone chooses to explore psilocybin, maintaining moderation, selecting safe company, and using verified products can help reduce avoidable risks. Never use alone, and if difficult psychological effects continue after the experience, it’s important to reach out for appropriate professional or peer support rather than trying to manage it in isolation.

References

1. National Institute on Drug Abuse. Psilocybin (Magic Mushrooms). nida.nih.gov. Published January 24, 2024. https://nida.nih.gov/research-topics/psilocybin-magic-mushrooms ↩︎
2. Hallucinogenic mushrooms drug profile | www.euda.europa.eu. www.euda.europa.eu. https://www.euda.europa.eu/publications/drug-profiles/hallucinogenic-mushrooms_en ↩︎
3. Yildirim B, Sahin SS, Gee A, et al. Adverse psychiatric effects of psychedelic drugs: a systematic review of case reports. Psychological Medicine. Published online November 20, 2024:1-13. doi:https://doi.org/10.1017/s0033291724002496 ↩︎
4. Müller F, Kraus E, Holze F, et al. Flashback phenomena after administration of LSD and psilocybin in controlled studies with healthy participants. Psychopharmacology. 2022;239. doi:https://doi.org/10.1007/s00213-022-06066-z ↩︎
5. Vis PJ, Goudriaan AE, ter Meulen BC, Blom JD. On Perception and Consciousness in HPPD: A Systematic Review. Frontiers in Neuroscience. 2021;15:675768. doi:https://doi.org/10.3389/fnins.2021.675768 ↩︎
6. Malcolm B, Thomas K. Serotonin toxicity of serotonergic psychedelics. Psychopharmacology. 2021;239. doi:https://doi.org/10.1007/s00213-021-05876-x ↩︎
7. Gukasyan N, Griffiths RR, Yaden DB, Antoine DG, Nayak SM. Attenuation of psilocybin mushroom effects during and after SSRI/SNRI antidepressant use. Journal of Psychopharmacology. 2023;37(7):026988112311799-026988112311799. doi:https://doi.org/10.1177/02698811231179910 ↩︎
8. Goodwin GM, Croal M, Feifel D, et al. Psilocybin for treatment-resistant depression in patients taking a concomitant SSRI medication. Neuropsychopharmacology. 2023;48(10):1-8. doi:https://doi.org/10.1038/s41386-023-01648-7 ↩︎
9. Perna J, Trop J, Palitsky R, et al. Prolonged adverse effects from repeated psilocybin use in an underground psychedelic therapy training program: a case report. BMC Psychiatry. 2025;25(1). doi:https://doi.org/10.1186/s12888-024-06303-z ↩︎
10. Gotvaldová K, Hájková K, Borovička J, Jurok R, Cihlářová P, Kuchař M. Stability of psilocybin and its four analogs in the biomass of the psychotropic mushroom Psilocybe cubensis. Drug Testing and Analysis. 2020;13(2). doi:https://doi.org/10.1002/dta.2950 ↩︎
11. National Center for Complementary and Integrative Health. Psilocybin for Mental Health and Addiction: What You Need To Know. NCCIH. Published May 2024. https://www.nccih.nih.gov/health/psilocybin-for-mental-health-and-addiction-what-you-need-to-know ↩︎
12. Szigeti B, Kaertner L, Blemings A, et al. Self-blinding citizen science to explore psychedelic microdosing. eLife. 2021;10:e62878. doi:https://doi.org/10.7554/eLife.62878 ↩︎