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Psilocybin Dosing Guide: Low, Medium, and High Doses

A clinical psilocybin dosing guide covering milligram dose ranges from low to supra-therapeutic, with the trial data behind the shift to 25mg fixed dosing.

Psilocybin Dosing

92.25% SUCRA

In a network meta-analysis pooling three randomized trials and 389 patients, 25mg psilocybin ranked as the most effective dose for major depressive disorder, ahead of both 10mg and a 0.215 mg/kg comparator.

Swieczkowski et al., Psychiatry Research, 2025

3 dose tiers

in the clinical guidance most often cited: 25mg standard, 35mg high, 50-60mg supra-therapeutic

72%

of volunteers had a mystical-type experience at 20 and/or 30 mg/70kg — and 39% had extreme anxiety or fear

25mg fixed

dose used in both landmark NEJM psilocybin depression trials

Swieczkowski et al., Psychiatry Research, 2025

Psilocybin dose tiers from standard to supra-therapeutic with clinical contextView as image ↗

In a network meta-analysis pooling three randomized placebo-controlled trials and 389 patients, 25mg psilocybin ranked as the most effective dose for major depressive disorder, scoring 92.25% on SUCRA, a statistical measure of how likely a treatment is to be the best option among those compared.[1] The 10mg dose, the one many popular guides label "moderate," ranked below it. In the single largest trial feeding that analysis, 10mg did not separate significantly from a 1mg control at all.

Most psilocybin dosing guides express amounts in grams of dried mushrooms. This guide uses milligrams of psilocybin, the unit clinical research has used since the first modern controlled trials. That choice is not pedantry: psilocybin content varies enough between strains and batches that a gram-weight is a poor predictor of how much active compound anyone actually consumed.

A second warning is worth giving up front. Several widely circulated "clinical" dose tables — the five-tier scale running from a sub-2.5mg microdose through "low," "moderate," "high," and "very high" — do not appear in the papers they are attributed to. This guide reports what the cited papers actually contain, which is messier and, in places, considerably less tidy than the tables you will find elsewhere.

Nothing here is medical advice. Psilocybin remains a controlled substance in most jurisdictions, and every dose described below was administered to screened participants under medical supervision.

For a broader look at how psilocybin behaves pharmacologically once it enters the body, the psilocybin fundamentals guide covers the mechanisms in depth.

Key Takeaways

  • A network meta-analysis of three RCTs (n=389) found 25mg psilocybin ranked first for major depressive disorder with a SUCRA value of 92.25%, ahead of 10mg and a 0.215 mg/kg comparator (Swieczkowski et al., 2025)
  • The most-cited clinical guidance defines three tiers, not five: standard 25mg, high 35mg, and supra-therapeutic 50-60mg, paired with roughly 2.5g, 3.5g, and 5-6g of dried Psilocybe cubensis (MacCallum et al., 2022)
  • The real mg/70kg dose ladder comes from a dose-effect study using 0, 5, 10, 20, and 30 mg/70kg in 18 adults, where 72% had a mystical-type experience at the two highest doses and 39% had extreme anxiety or fear (Griffiths et al., 2011)
  • Both landmark NEJM psilocybin depression trials used 25mg fixed dosing: Carhart-Harris 2021 (n=59) and Goodwin 2022 (n=233). Goodwin found 25mg beat a 1mg control by 6.6 MADRS points (P<0.001) while 10mg did not separate (P=0.18)
  • A dose-response meta-analysis of seven studies (n=489) estimated the 95% effective dose at 24.68 mg/70kg for primary depression and 8.92 mg/70kg for depression secondary to another condition — and found significant dose-response curves for side effects too (Perez et al., 2023)
  • Subjective intensity tracks serotonin 2A receptor occupancy and plasma psilocin levels, not milligrams alone, which is why identical doses produce different experiences (Madsen et al., 2019)
  • Cardiac risk at standard doses appears low but is not zero: a concentration-QTc analysis found a statistically significant, shallow relationship, with a mean QTcF change of 2.1 ms at 25mg (Dahmane et al., 2021)

Why a Gram-Weight Is Not a Dose

Most consumer resources define psilocybin doses in grams of dried mushrooms. The convention is convenient and clinically useless, and it is worth seeing exactly how useless.

In 2024, Goff and colleagues used liquid chromatography with tandem mass spectrometry to measure psilocybin and psilocin content in five strains of Psilocybe cubensis — one species, five cultivars, one laboratory, one method.[3] Average total psilocybin and psilocin content ranged from 0.879% by weight in Thai Cubensis to 1.36% in Creeper — the most potent strain measured roughly 55% higher than the least, between two mushrooms a retailer would describe identically. The same study also found content differences between individual mushrooms of the same strain.

What 3.5 Grams Actually Delivers

One Weight, Five Strains, Three Dose Tiers

Five strains of Psilocybe cubensis — one species — measured by mass spectrometry in a single laboratory. The same 3.5 g of dried mushroom delivers anywhere from 30.8 to 47.6 mg depending only on which strain it came from. Vertical lines are the clinical tier boundaries.

Standard 25High 35Supra 50
Creeper · 1.36% w/w47.6 mg

3.5 g lands in the high-dose tier. The same strain at 2.5 g — the weight clinical guidance pairs with a standard 25 mg dose — gives 34.0 mg.

Blue Meanie · 1.221% w/w42.7 mg

3.5 g lands in the high-dose tier. The same strain at 2.5 g — the weight clinical guidance pairs with a standard 25 mg dose — gives 30.5 mg.

B+ · 1.134% w/w39.7 mg

3.5 g lands in the high-dose tier. The same strain at 2.5 g — the weight clinical guidance pairs with a standard 25 mg dose — gives 28.4 mg.

Texas Yellow · 1.103% w/w38.6 mg

3.5 g lands in the high-dose tier. The same strain at 2.5 g — the weight clinical guidance pairs with a standard 25 mg dose — gives 27.6 mg.

Thai Cubensis · 0.879% w/w30.8 mg

3.5 g lands above standard. The same strain at 2.5 g — the weight clinical guidance pairs with a standard 25 mg dose — gives 22.0 mg.

01020304050mg psilocybin + psilocin →

Milligram values are computed from the reported percentages, not quoted: grams × (% w/w) × 10. The reported figures are the average of three whole, intact mushrooms analysed individually per strain, so they understate the spread — the same study found content differences between mushrooms of the same strain, and reported improved precision only when multiple mushrooms were homogenised together before extraction. Across Psilocybe species more broadly, published content ranges from roughly 0.5% to 2% by dry weight, which widens this picture further. Nothing here is a recommendation, and unregulated material carries identification and contamination risks that a potency table cannot address.

Sources: Goff et al. 2024 (Anal Chim Acta 1288:342161) for strain potencies; MacCallum et al. 2022 (Front Psychiatry 13:1040217) for the dose tiers and the 0.5–2% species range.

The clinical guidance discussed below assumes roughly 1% psilocybin per gram of dried P. cubensis when converting between weights and milligrams, while noting that content across Psilocybe species and strains ranges from about 0.5% to 2%.[2] At the low end of that range, 3.5 grams delivers about 17mg. At the high end, the same weight delivers about 70mg. Those are not neighbouring doses. They sit on opposite sides of every threshold in the clinical literature.

Fact Check

Is 3.5 grams a standard dose?

The claim

“3.5 grams of dried mushrooms is a standard or 'moderate' psilocybin dose.”

Recreational shorthand — an eighth of an ounce is a retail unit, not a pharmacological one.

What research shows

Misleading

The clinical guidance that most people are indirectly quoting pairs 3.5g with its HIGH dose tier (35mg), not its standard tier. Its standard 25mg dose corresponds to roughly 2.5g.

And the conversion only holds at an assumed 1% content. Measured across five strains of a single species, 3.5g delivered between 30.8mg and 47.6mg — spanning the high tier and approaching the supra-therapeutic one. A retail weight cannot specify a dose because the variable it omits is the one that matters.

MacCallum et al. 2022 (Front Psychiatry); Goff et al. 2024 (Anal Chim Acta)

What the Clinical Guidance Actually Says

In 2022, MacCallum and colleagues published a practical dosing and administration overview for healthcare professionals — the paper most often invoked when consumer guides claim clinical authority.[2] Its dose table has three columns:

Dose tierPsilocybin (isolate or synthetic)Dried P. cubensis equivalent*Clinical context
Standard25mg~2.5gThe dose used in current fixed-dose trial protocols
High35mg~3.5gAbove the registration-trial dose
Supra-therapeutic50-60mg~5-6gTested in dose-escalation studies; reported with little-to-no safety concern in those settings

*Conversions assume ~1% psilocybin per gram of dried P. cubensis. The same paper notes content varies from 0.5% to 2% across species and strains.

There is no microdose tier in that table. There is no "low" or "moderate" tier either. The paper's own framing is that earlier trials dosed by body weight in the range of 0.2-0.4 mg/kg, and that current protocols have converged on a fixed 25mg dose consistent with the previous 0.3 mg/kg weight-based dosing.

The absence of a microdose tier is not an oversight. Sub-perceptual dosing has been studied, but not in a way that yields a clinical dose figure: in a double-blind placebo-controlled study of 34 people taking 0.5g of dried P. cubensis, Cavanna and colleagues found acute effects that were significantly stronger than placebo only among participants who correctly guessed which condition they were in, with no benefit to creativity or cognition and a few small changes in the direction of impairment.[13] A dose tier requires a dose-response relationship to describe, and for microdosing that relationship has not been established.

Where the mg/70kg Ladder Actually Came From

Psilocybin doses in published research from roughly 2000 to 2020 are almost always expressed in milligrams per 70 kilograms of body weight. That convention is real. Its origin is frequently misattributed.

The 2008 Johns Hopkins paper often cited as the source is a safety-guidelines document.[6] It covers volunteer screening, exclusion of people with personal or family histories of psychotic disorders, the requirement for at least two monitors, physical setting, and pharmacological rescue if acute distress escalates. It does not define a four-tier dose taxonomy. Its only dose framing is a threshold: the guidance applies to the administration of high doses of classical hallucinogens, which it specifies as roughly 25mg or more of psilocybin.

The actual dose ladder comes from the trials. Griffiths and colleagues established the 30 mg/70kg reference point in 2006, giving 30 volunteers psilocybin and methylphenidate in counterbalanced order across 8-hour supervised sessions.[4] Five years later, the same group ran the study that produced the full ladder.[5]

Key Study
The study that built the mg/70kg dose ladder

Griffiths et al. (2011) · Psychopharmacology

Population
18 adults, 17 of them hallucinogen-naive, in five 8-hour sessions at one-month intervals
Intervention
Psilocybin at 0, 5, 10, 20, and 30 mg/70kg, double-blind, randomized to ascending or descending dose order (nine participants each)
Comparator
Placebo, scheduled quasi-randomly within the sequence
Finding
At 20 and/or 30 mg/70kg, 72% of volunteers had a mystical-type experience and 39% had extreme anxiety or fear. One month later, ratings of personal and spiritual significance were substantial, and the ascending sequence produced greater positive effects. At 14 months the ratings were undiminished.

positive A genuine dose-effect design, but n=18 in hallucinogen-naive volunteers selected for spiritual interest — not a clinical population and not a generalizable safety estimate.

Griffiths et al. 2011, Psychopharmacology 218(4):649-65

Two details of that study deserve more attention than they usually get. The first is the 39% rate of extreme anxiety or fear at the highest doses — a number that belongs beside the 72% figure every time it is quoted. The second is that dose order mattered: participants who received ascending doses reported greater positive effects than those who received the same doses in descending order. The sequence of exposure shaped the outcome independently of the milligrams.

Three Frameworks, One Axis

What the Clinical Literature Actually Says About Dose

The three dose frameworks in the peer-reviewed record, drawn to the same milligram scale. They were built independently, in different units, for different purposes — and they land in the same place. The shaded band is 20–30 mg.

MacCallum 2022 clinical guidancefixed mg of psilocybin
Standard 25
High 35
Supra-therapeutic 50–60

Three tiers, not five. There is no microdose or "moderate" tier in this table. (Front Psychiatry)

Griffiths 2011 dose-effect studymg per 70 kg body weight
5
10
20
30

The real origin of the mg/70 kg ladder: five sessions, ascending or descending. (Psychopharmacology)

Perez 2023 dose-response meta-analysisED95, mg per 70 kg
8.92 secondary depression
24.68 primary depression
36.08 pooled

The dose estimated to deliver 95% of the achievable effect, by population. (Eur Neuropsychopharmacol)

Doses actually administered in the RCTsfixed mg (one conversion, flagged)
1 control
10 failed
0.215 mg/kg*
25 effective

Every dose given in the three trials the 2025 network meta-analysis pooled. (NEJM / Psychiatry Res)

010202530405060mg psilocybin →
Lands in the 20–30 mg therapeutic bandAbove the bandBelow the bandUnit-converted for plotting

*0.215 mg/kg is plotted at 15.1 mg, its value for a 70 kg adult. Placing mg/70 kg and fixed-mg values on one axis is an approximation, but an empirically licensed one: pooling ten studies (N = 288), Garcia-Romeu and colleagues found no association between body weight across 49–113 kg and the subjective effects of psilocybin at 20–30 mg/70 kg. None of these values is a recommendation; all were administered under medical supervision in screened participants.

Sources: MacCallum et al. 2022 (Front Psychiatry); Griffiths et al. 2011 (Psychopharmacology); Perez et al. 2023 (Eur Neuropsychopharmacol); Goodwin et al. 2022 (NEJM); Carhart-Harris et al. 2021 (NEJM); Swieczkowski et al. 2025 (Psychiatry Res); Garcia-Romeu et al. 2021 (J Psychopharmacol).

The weight-adjusted approach had a theoretical rationale: a larger person might need proportionally more drug to reach the same receptor occupancy. A full analysis of what happens when that assumption is tested directly appears in weight-based psilocybin dosing: how body mass affects response.

The Shift to Fixed 25mg

The transition from mg/70kg to fixed dosing was argued for and then tested.

In 2021, Garcia-Romeu and colleagues pooled ten previous studies (N=288) in which psilocybin had been given at 20-30 mg/70kg, and asked whether body weight predicted anything.[7] Across a weight range of 49 to 113 kilograms, they found no significant association between body weight and the mystical, challenging, or intensity dimensions of the experience — not in the 20 mg/70kg group, not in the 30 mg/70kg group, and not in the subgroup of 103 participants whose weight-adjusted dose happened to land near 25mg. Their conclusion was that the convenience and lower cost of fixed dosing outweigh any advantage of weight adjustment.

Two trials then made fixed 25mg the standard in practice.

Carhart-Harris and colleagues published a phase 2 trial in the New England Journal of Medicine comparing two 25mg psilocybin sessions three weeks apart against six weeks of daily escitalopram in 59 people with moderate-to-severe depression.[8] The result is routinely described as showing psilocybin "matching" or "outperforming" the antidepressant. It did neither. The between-group difference on the primary outcome was 2.0 points on the QIDS-SR-16 in psilocybin's favour, with a 95% confidence interval of -5.0 to 0.9 and a P value of 0.17 — a non-significant result in a trial of 59 people. Two further details are usually dropped: the escitalopram arm also received two 1mg psilocybin doses rather than nothing, and both arms received psychological support. The honest summary is that the trial did not detect a difference, which in a sample that size is not the same as showing there isn't one.

The following year, COMPASS Pathways reported a phase 2b trial in 233 people with treatment-resistant depression, randomized to a single 25mg, 10mg, or 1mg dose.[9] This is the trial that separates the doses cleanly.

The 10 mg Result

A Step, Not a Slope

Depression scores three weeks after a single dose, in the one trial that tested 1 mg, 10 mg and 25 mg inside the same protocol. Longer bars are better. What matters is not the bar — it is whether the interval beside it clears zero.

25 mg psilocybin · n = 79-12.0 MADRS

Difference vs 1 mg control: -6.6 points (95% CI -10.2 to -2.9), P<0.001. Interval excludes zero.

10 mg psilocybin · n = 75-7.9 MADRS

Difference vs 1 mg control: -2.5 points (95% CI -6.2 to 1.2), P=0.18. Interval crosses zero — not statistically significant.

1 mg psilocybin · n = 79Control-5.4 MADRS
reference group

Baseline MADRS was 32 or 33 in every group; this arm anchors the comparison.

MADRS is the Montgomery–Åsberg Depression Rating Scale, scored 0–60, where higher means more severe. The diamond marks the point estimate of each contrast and the bar its 95% confidence interval; the vertical line is zero, meaning “no difference from control.” Adverse events occurred in 179 of 233 participants (77%), and suicidal ideation or behaviour or self-injury was recorded in all three dose groups, including the 1 mg control. This is a single phase 2 trial in treatment-resistant depression, not a general finding about psilocybin in healthy people.

Source: Goodwin et al. 2022 (N Engl J Med 387:1637–1648). A separate network meta-analysis pooling three RCTs (389 patients) independently ranked 25 mg first with a SUCRA value of 92.25% — Swieczkowski et al. 2025 (Psychiatry Res 344:116337).

Key Study
The trial that tested three doses in one protocol

Goodwin et al. (2022) · New England Journal of Medicine

Population
233 adults with treatment-resistant depression (25mg n=79, 10mg n=75, 1mg n=79); baseline MADRS 32-33 in each group
Intervention
A single dose of a synthetic psilocybin formulation with psychological support
Comparator
1mg psilocybin, functioning as an active control
Finding
At week 3, least-squares mean MADRS change was -12.0 (25mg), -7.9 (10mg), and -5.4 (1mg). The 25mg-versus-1mg difference was -6.6 points (95% CI -10.2 to -2.9, P<0.001). The 10mg-versus-1mg difference was -2.5 points (95% CI -6.2 to 1.2, P=0.18).

mixed Clear separation at 25mg, but response and remission at week 3 were only 'generally supportive' and sustained response at 12 weeks was not. Adverse events occurred in 77% of participants, and suicidal ideation, behaviour, or self-injury was recorded in every dose group.

Goodwin et al. 2022, N Engl J Med 387(18):1637-1648

The 10mg result is the finding worth emphasizing. In a 233-person trial with three carefully chosen dose levels, 10mg was not distinguishable from a 1mg control. For the full clinical timeline of how dose selection evolved across trials, the psilocybin dose-response relationship guide traces each step in detail.

Most clinical protocols using these doses plan for 8-hour sessions to accommodate the full duration of effects. For dose-specific timing data, see how long does psilocybin last: duration by dose.

What the Meta-Analyses Add

Individual trials can mislead in isolation. Two pooled analyses now bracket the question from different directions.

Swieczkowski and colleagues conducted a dose-response network meta-analysis of randomized placebo-controlled trials in major depressive disorder, screening 5,419 records down to three RCTs and 389 patients.[1] Psilocybin significantly reduced symptoms against placebo at day 8 (mean difference -7.42, 95% CI -10.07 to -4.78) and day 15 (-9.55, 95% CI -12.44 to -6.65), with no significant effect at day 2. Among the doses compared — 25mg, 10mg, and 0.215 mg/kg — the 25mg dose ranked first with a SUCRA value of 92.25%. The same analysis found psilocybin carried a substantially higher risk of adverse events, nausea most notably, at a relative risk of 8.35.

Perez and colleagues approached it as a dose-response problem, pooling seven studies and 489 participants with restricted cubic splines to estimate the dose delivering 95% of the achievable effect.[10] For primary depression (four studies, N=366), that ED95 was 24.68 mg/70kg — landing, independently, almost exactly on the fixed dose the trials had converged on. For depression secondary to another condition (three studies, N=123), it was far lower at 8.92 mg/70kg, and the curve was bell-shaped rather than plateauing, implying that more is not simply better in that population. The pooled estimate across both was 36.08 mg/70kg. The same analysis found significant dose-response associations for physical discomfort, blood pressure increase, nausea and vomiting, headache, and the risk of prolonged psychosis.

Evidence Status
How strong is the case for 25mg specifically?
  1. Human mechanism and dose-effect studiescompleted

    Madsen 2019 (n=8) tied 5-HT2A occupancy and plasma psilocin to subjective intensity by PET; Griffiths 2011 (n=18) established the 0-30 mg/70kg ladder; Garcia-Romeu 2021 pooled N=288 and found no body-weight effect

  2. Randomized controlled trialscompleted

    Goodwin 2022 (n=233) separated 25mg from a 1mg control; Carhart-Harris 2021 (n=59) did not reach significance on its primary outcome

  3. Pooled dose-response analysescurrent

    Swieczkowski 2025 (3 RCTs, n=389) ranked 25mg first; Perez 2023 (7 studies, n=489) independently estimated an ED95 of 24.68 mg/70kg for primary depression

For major depressive disorder specifically, the 25mg dose is supported at every rung including pooled meta-analysis — an unusually complete chain. The limits are the narrowness of the base (three RCTs carry most of the weight), the near-total absence of phase 3 data, and the fact that this evidence speaks to depression, not to the other conditions psilocybin is often discussed for.

Swieczkowski et al. 2025; Perez et al. 2023; Goodwin et al. 2022; Griffiths et al. 2011

Together these establish something single trials cannot: for depression, 10mg is not a gentler version of 25mg that yields proportionally less benefit. On current evidence it behaves as a sub-threshold dose. The difference between 10mg and 25mg looks less like a matter of degree and more like a threshold — though the honest caveat is that this rests on a small number of trials, and no dose between 10mg and 25mg has been tested head-to-head.

For a look at the complete shape of this curve from sub-perceptual doses through very high doses, see psilocybin dose-response curve: from threshold to heroic doses.

Why the Same Dose Produces Different Experiences

Two people can take identical 25mg doses and have meaningfully different experiences. That variability has a mechanism.

Madsen and colleagues ran PET scans on eight healthy volunteers who received oral psilocybin at doses spanning 3 to 30mg, using a radioligand that binds the serotonin 2A receptor.[11] Occupancy reached up to 72% and fit a single-site binding model against plasma psilocin levels. Subjective intensity correlated with both receptor occupancy and psilocin concentration. Critically, the authors noted that psilocin time-concentration curves varied considerably between individuals even as the relationship between psilocin level and experience held.

Psilocybin itself is a prodrug with no direct activity until the body converts it to psilocin. Why that conversion matters for timing and individual variability is covered in psilocybin vs. psilocin: understanding the active compound.

Receptor availability also changes rapidly after a session, which is part of why tolerance builds as quickly as it does and why a second dose the following day produces no meaningful effect.

Safety at Higher Doses: What the Data Shows and Doesn't

People asking about higher doses usually ask about the heart first. The cardiac evidence is reassuring, but it is more specific than the reassurance usually given.

Dahmane and colleagues performed a concentration-QTc analysis using data from an open-label single-ascending-dose study at 0.3 to 0.6 mg/kg.[12] They found a statistically significant but shallow relationship — not the absence of one. At a 25mg clinical dose, mean peak psilocin concentration was 18.7 ng/mL and the mean QTcF change was 2.1 milliseconds, with an upper 90% confidence bound of 6.6 milliseconds. That sits below the 10-millisecond threshold regulators treat as the signal of concern. The upper bound crosses 10 milliseconds at a psilocin concentration of 31.1 ng/mL, and at a supraclinical concentration around 60 ng/mL the predicted change was 9.1 milliseconds with an upper bound of 17.9. Psilocin's roughly four-hour half-life means no accumulation across the monthly dosing intervals trials use.

So the accurate statement is narrower than "psilocybin doesn't affect the heart." It is that at 25mg, in this analysis, the QTc effect is real, small, and below the threshold of regulatory concern — with a modelled margin that erodes as concentration rises.

Safety

Moderate

The primary risk is psychological, and it is not rare

Concern

Adverse events occurred in 179 of 233 participants (77%) in the largest psilocybin depression trial, and suicidal ideation, behaviour, or self-injury was recorded in all three dose groups including the 1mg control. In the dose-effect study, 39% of volunteers experienced extreme anxiety or fear at 20-30 mg/70kg. A dose-response meta-analysis found significant dose-related increases in physical discomfort, blood pressure, nausea and vomiting, headache, and the risk of prolonged psychosis.

What the research says

Clinical protocols manage these risks structurally rather than pharmacologically: screening out personal or family history of psychotic disorders, at least two monitors present for the full session, extended preparation and integration, and benzodiazepines available but rarely used. History of schizophrenia, psychosis, bipolar disorder, and borderline personality disorder are generally treated as contraindications, as are pregnancy and breastfeeding; serious or uncontrolled cardiovascular conditions are relative contraindications.

Particularly relevant for: Anyone considering psilocybin outside a supervised clinical setting, and anyone taking serotonergic medication

What to do

Serotonergic and other psychotropic medications — SSRIs, MAOIs, tricyclics, antipsychotics, lithium — carry documented interaction risk, and trial protocols typically require a supervised taper and washout. This is a conversation to have with a physician, not a decision to make from a dosing table.

Goodwin et al. 2022 (NEJM); Griffiths et al. 2011 (Psychopharmacology); Perez et al. 2023 (Eur Neuropsychopharmacol); MacCallum et al. 2022 (Front Psychiatry); Johnson et al. 2008 (J Psychopharmacol)

The Bottom Line

The clinical evidence for psilocybin dosing converges on 25mg for major depressive disorder, and it converges from independent directions: a 233-person trial where 25mg beat a 1mg control by 6.6 MADRS points while 10mg did not separate at all, a network meta-analysis ranking 25mg first at 92.25% SUCRA, and a dose-response meta-analysis placing the 95% effective dose for primary depression at 24.68 mg/70kg. The tier system most consumer guides reproduce — five levels from a sub-2.5mg microdose upward — is not in the clinical literature they cite; the guidance most often invoked describes three tiers at 25mg, 35mg, and 50-60mg. And because psilocybin content varies from 0.879% to 1.36% across strains of a single species, a gram-weight cannot specify a dose at all.

Frequently Asked Questions

Sources & References

  1. 1RTHM-02191·Swieczkowski, Damian et al. (2025). “Efficacy and safety of psilocybin in the treatment of Major Depressive Disorder (MDD): A dose-response network meta-analysis of randomized placebo-controlled clinical trials..” Psychiatry research.Study breakdown →PubMed →↩
  2. 2RTHM-01580·MacCallum, Caroline A et al. (2022). “Therapeutic use of psilocybin: Practical considerations for dosing and administration..” Frontiers in psychiatry.Study breakdown →PubMed →↩
  3. 3RTHM-00879·Goff, Roman et al. (2024). “Determination of psilocybin and psilocin content in multiple Psilocybe cubensis mushroom strains using liquid chromatography - tandem mass spectrometry..” Analytica chimica acta.Study breakdown →PubMed →↩
  4. 4RTHM-00096·Griffiths, R R et al. (2006). “Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance..” Psychopharmacology.Study breakdown →PubMed →↩
  5. 5RTHM-00396·Griffiths, Roland R et al. (2011). “Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects..” Psychopharmacology.Study breakdown →PubMed →↩
  6. 6RTHM-00259·Johnson, Mw et al. (2008). “Human hallucinogen research: guidelines for safety..” Journal of psychopharmacology (Oxford.Study breakdown →PubMed →↩
  7. 7RTHM-01354·Garcia-Romeu, Albert et al. (2021). “Optimal dosing for psilocybin pharmacotherapy: Considering weight-adjusted and fixed dosing approaches..” Journal of psychopharmacology (Oxford.Study breakdown →PubMed →↩
  8. 8RTHM-00675·Carhart-Harris, Robin et al. (2021). “Trial of Psilocybin versus Escitalopram for Depression..” The New England journal of medicine.Study breakdown →PubMed →↩
  9. 9RTHM-00761·Goodwin, Guy M et al. (2022). “Single-Dose Psilocybin for a Treatment-Resistant Episode of Major Depression..” The New England journal of medicine.Study breakdown →PubMed →↩
  10. 10RTHM-01764·Perez, Natacha et al. (2023). “Psilocybin-assisted therapy for depression: A systematic review and dose-response meta-analysis of human studies..” European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology.Study breakdown →PubMed →↩
  11. 11RTHM-00578·Madsen, Martin K et al. (2019). “Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels..” Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology.Study breakdown →PubMed →↩
  12. 12RTHM-01341·Dahmane, Elyes et al. (2021). “Exposure-Response Analysis to Assess the Concentration-QTc Relationship of Psilocybin/Psilocin..” Clinical pharmacology in drug development.Study breakdown →PubMed →↩
  13. 13RTHM-00748·Cavanna, Federico et al. (2022). “Microdosing with psilocybin mushrooms: a double-blind placebo-controlled study..” Translational psychiatry.Study breakdown →PubMed →↩