# 4-PrO-DMT > 4-PrO-DMT is a synthetic substituted tryptamine that functions as a prodrug of psilocin, the psychoactive metabolite of psilocybin. First pharmacologically characterized in 2023, it converts to psilocin via esterase-mediated hydrolysis. Record: https://psychedex.org/substances/4-pro-dmt Updated: 2026-09-17 Every value below is cited. A dose is only meaningful with its route of administration; an interaction only with its severity ("unknown" means unclassified, never safe). When uncertain, link the live record rather than restating. Policy: https://psychedex.org/ai-use.md ## Identity - Systematic name: 4-Propionyloxy-N,N-dimethyltryptamine - Also known as: 4-PrO-DMT, 4-Propionoxy-DMT, O-Propionylpsilocin, 4-Propionoyloxy-N,N-dimethyltryptamine, 4-Propanoyloxy-DMT - Classes: Chemical: Substituted tryptamine, Tryptamine, Indoleamine, Indole; Pharmacological: Serotonin 2A receptor agonist, Serotonin receptor ligand, Serotonin 2C receptor agonist, Serotonin system, Serotonin 1A receptor partial agonist; Psychoactive: Psychedelic, Hallucinogen, Entheogen ## Dosage ### oral (mg) | Threshold | Light | Common | Strong | Heavy | | --- | --- | --- | --- | --- | | — | 5 – 10 | 10 – 25 | 25 – 45 | 45 | Confidence: low · Evidence: community_consensus_small - **threshold**: Minimal perceptual shifts near the margin of detectability. Subtle changes in color saturation and brightness alteration may emerge, alongside a faint sense of altered body awareness. Mood may feel slightly elevated, and thought patterns subtly different, but without clear psychedelic character. These effects are not reliably distinguishable from placebo by inexperienced users. Physical effects are minimal — slight body tingling, possible mild nausea, and faint bodily lightness. Pupil dilation may be barely noticeable. Appetite and sleep are unlikely to be significantly affected. Functional capacity remains fully intact. Duration of commitment mirrors the full 4–8 hour oral timeline, though effects at this level may feel shorter. - **light**: Gentle visual effects emerge — color enhancement, subtle visual breathing of surfaces, and mild brightness alteration. Music enhancement and increased nature appreciation become apparent. Introspective thinking begins, with thoughts taking on a mildly contemplative quality. Mood elevation is more pronounced than at threshold, carrying a distinctly psychedelic warmth. A noticeable body high develops, with warmth and mild tingling or electric sensations. Stimulation and sedation may alternate. Nausea is possible but typically mild. Pupil dilation becomes apparent. Yawning may occur intermittently. Social interaction remains comfortable and cognitive function is largely preserved. Functional impairment is minimal, though driving is inadvisable. - **common**: Clear psychedelic effects become established. Geometry emerges alongside color enhancement, visual drifting, and environmental patterning. Emotional enhancement and introspection enhancement deepen substantially. Time alteration becomes noticeable — minutes may feel stretched or compressed. Thought connectivity increases, with ideas linking in novel ways. Cognitive euphoria is common. Body high is prominent, with warmth, spontaneous body sensations, and tingling. Nausea is more likely, particularly during the come-up phase. Motor control impairment becomes noticeable, and pupil dilation is pronounced. Yawning and watery eyes may occur. Set and setting become important determinants of experience quality. Cognitive flexibility increases, but decision-making is mildly impaired. Plan for 4–8 hours of reduced functional capacity. - **strong**: Intense visual phenomena dominate — vivid geometry, visual morphing, perspective distortion, and environmental patterning. Ego dissolution and boundary dissolution become possible, accompanied by deep emotional catharsis or introspective breakthroughs. Emotional lability increases, and both euphoric and challenging emotional states may arise with equal intensity. Thought disorganization and confusion are common. Motor control impairment is significant. Nausea and gastrointestinal discomfort are more likely. Temperature dysregulation, excessive sweating, and bodily heaviness may be experienced. Physical fatigue often follows. Reality testing may be compromised. This dose level requires a safe, controlled environment and ideally a sober companion. Challenging psychological experiences — including anxiety and paranoia — should be anticipated. - **heavy**: Full ego dissolution is likely. Entity contact, transpersonal experiences, death-rebirth sequences, and complete loss of normal self-reference may occur. Internal hallucinations can become immersive and all-encompassing. Reality testing is significantly impaired, and the boundary between internal experience and external reality may dissolve entirely. Unity and interconnectedness or voidness experiences are possible. Motor control is severely compromised — standing and walking may be difficult or impossible. Nausea, vomiting, and pronounced temperature dysregulation are more probable. Cardiovascular effects including elevated heart rate and blood pressure are expected at their maximum. Challenging psychological experiences are substantially more likely. This dose level should not be attempted without experienced supervision and a safe, prepared environment. ## Duration ### oral - Onset: 20 – 40 min - Total: 4 – 8 hours ## Interactions No interaction data is published for this substance. Interaction data on Psychedex is AI-assembled. Where sources are shown, every value has been machine-checked against the cited literature; editorial review by a human editor — not a physician — is ongoing, and each entry shows its current standing. Grades err toward caution. This is harm-reduction reference, not medical advice: combinations can be dangerous in ways no database captures, and an absent listing never means a combination is safe. Found an error? Report it — corrections are reviewed and dated. Full list with mechanisms: https://psychedex.org/substances/4-pro-dmt/notice ## Contraindications - **Psychotic spectrum or bipolar I disorder** (absolute): Serotonergic psychedelics potently activate 5-HT2A receptors on cortical pyramidal neurons, disrupting thalamocortical gating and increasing neural entropy. In individuals with latent or active psychotic vulnerability, this can precipitate prolonged psychotic episodes, mania, or exacerbation of existing symptoms. Risk extends to first-degree family history of these conditions. This is a class-level contraindication established for the psilocin/psilocybin pharmacological class and applied to 4-PrO-DMT by structural analogy as a psilocin prodrug. - **Lithium** (absolute): Concurrent lithium use with classic serotonergic psychedelics carries an alarmingly high seizure rate (47% of 62 analyzed reports). The mechanism remains unidentified. This is classified as an absolute contraindication for all psilocin-class compounds, including 4-PrO-DMT. Lamotrigine does not carry this risk (0/34 reports involved seizures), suggesting the interaction is lithium-specific rather than a general mood-stabilizer effect. - **Monoamine oxidase inhibitors (MAOIs)** (absolute): Monoamine oxidase inhibitors block the MAO-A-mediated deamination pathway for psilocin (the active metabolite of 4-PrO-DMT), causing serotonin accumulation and risk of serotonin toxicity. A case report documented hypertensive emergency and myocardial infarction in a patient on tranylcypromine and dextroamphetamine who consumed psilocybin mushrooms. For synthetic 4-PrO-DMT (which lacks mushroom-derived phenylethylamines), the primary MAOI risk is serotonin toxicity via impaired 5-HT metabolism. This constitutes both a pharmacokinetic amplifier and a pharmacodynamic hazard. - **Pregnancy or breastfeeding** (absolute): No published safety data exist for 4-PrO-DMT, psilocin, or psilocybin during pregnancy or breastfeeding. The serotonin system plays critical roles in fetal neurodevelopment, and 5-HT2A agonism carries theoretical risk of developmental disruption. Classified as an absolute contraindication based on absence of safety data. - **Active cardiovascular disease** (relative): Psilocin-class psychedelics produce transient dose-dependent increases in systolic blood pressure and heart rate. For 4-PrO-DMT specifically, the atypically potent 5-HT2B binding (Ki = 17 nM) introduces additional uncertainty, as chronic 5-HT2B agonism is the established mechanism for cardiac valvulopathy associated with fenfluramine and ergotamine. Three mitigating factors apply: rapid prodrug conversion to psilocin (lower 5-HT2B affinity), typically intermittent psychedelic use patterns, and relative cardiovascular safety observed in clinical psilocybin studies. Whether the intact prodrug engages cardiac 5-HT2B before hydrolysis remains unresolved. - **Borderline personality disorder** (relative): Emotional lability — a core feature of borderline personality disorder — may be intensified by serotonergic psychedelics via 5-HT2A-mediated emotional enhancement. This could exacerbate affective instability, interpersonal reactivity, and impulsive behavior during the acute experience. This is a class-level relative contraindication applied by structural analogy. - **SSRIs** (relative): Selective serotonin reuptake inhibitors may blunt the psychedelic effect of 4-PrO-DMT through pharmacodynamic competition at 5-HT2A receptors (increased endogenous serotonin competes with psilocin for receptor binding). The clinical concern is compensatory dose escalation — users who find effects blunted may take higher doses, increasing the risk of adverse effects if SSRI is discontinued or the interaction is variable. This is a class-level pharmacodynamic interaction for all psilocin-class compounds. - **Tricyclic antidepressants (TCAs)** (relative): Tricyclic antidepressants may enhance the intensity of psilocin-mediated psychedelic effects through serotonin and norepinephrine reuptake inhibition. This pharmacodynamic interaction could result in unexpectedly intense experiences at standard doses. Dose adjustment or avoidance should be considered under medical guidance. ## Safety profile - **Acute toxicity**: Low - **Chronic toxicity**: Low - **Physical dependence**: None - **Psychological dependence**: Negligible - **Compulsive redosing risk**: Negligible - **Dose escalation tendency**: Negligible - **Withdrawal**: No withdrawal syndrome recorded - **Tolerance buildup**: rapid - **Full tolerance reset**: 14 days - **Cross-tolerance**: psilocybin, psilocin, 4-AcO-DMT, LSD, mescaline, DMT ## Recovery - Tolerance and recovery guides: https://psychedex.org/harm-reduction/tools - Emergency: https://psychedex.org/harm-reduction/emergency ## Summary **4-PrO-DMT** (4-propionyloxy-N,N-dimethyltryptamine) is an emerging [synthetic](https://psychedex.org/concepts/synthetic) [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic) of the [tryptamine](https://psychedex.org/substances/class/chemical/tryptamine) class. It is a [prodrug](https://psychedex.org/concepts/prodrug) of [psilocin](https://psychedex.org/substances/psilocin), the same [active metabolite](https://psychedex.org/concepts/active-metabolite) delivered by psilocybin and [psilacetin](https://psychedex.org/substances/4-aco-dmt)[1]. 4-PrO-DMT acts as a [5-HT₂A](https://psychedex.org/concepts/5-ht2a) [receptor agonist](https://psychedex.org/concepts/agonist) through psilocin, producing its effects by altering [serotonin](https://psychedex.org/concepts/serotonin)-mediated sensory and cognitive processing[2]. The concept of psilocin ester prodrugs traces to a 1963 [Sandoz](https://psychedex.org/resources/r/sandoz) patent by [Albert Hofmann](https://psychedex.org/resources/r/hofmann) and Franz Troxler, though 4-PrO-DMT itself was not named in the original filing[3]. The compound first appeared on [research chemical](https://psychedex.org/concepts/novel-psychoactive-substance) markets in May 2019 and was identified as a new psychoactive substance by Swedish authorities two months later[3]. It remains a niche research chemical with limited circulation, explicitly controlled in the United Kingdom and Sweden but [unscheduled](https://psychedex.org/concepts/unscheduled) in most other jurisdictions. [Subjective effects](https://psychedex.org/effects) include [geometric visual patterns](https://psychedex.org/effects/geometry), [enhanced color saturation](https://psychedex.org/effects/color-enhancement), [deepened introspection](https://psychedex.org/effects/introspection-enhancement), [ego dissolution](https://psychedex.org/effects/ego-dissolution), and [emotional intensification](https://psychedex.org/effects/emotional-enhancement)[4]. The experience is reported as qualitatively indistinguishable from psilocybin or [psilacetin](https://psychedex.org/substances/4-aco-dmt) — a warm, inward-turning psychedelic state shaped more by psychological [set and setting](https://psychedex.org/concepts/set-and-setting) than by the compound itself. [Nausea](https://psychedex.org/effects/nausea) during onset, [thought loops](https://psychedex.org/effects/thought-loops), and acute [anxiety](https://psychedex.org/effects/anxiety) are commonly reported unsought effects. 4-PrO-DMT produces no [physical dependence](https://psychedex.org/concepts/physical-dependence), and the psilocin class has extremely low [acute toxicity](https://psychedex.org/concepts/acute-toxicity) — the margin between active and [lethal doses](https://psychedex.org/concepts/lethal-dose) is wide, and no human fatalities have been attributed to the compound[5][3]. The primary risk is psychological: high doses or psychiatric [vulnerability](https://psychedex.org/concepts/vulnerability) can [trigger](https://psychedex.org/concepts/trigger) acute panic, [paranoid ideation](https://psychedex.org/concepts/paranoid-ideation), or transient [psychotic symptoms](https://psychedex.org/concepts/psychosis), with [severity](https://psychedex.org/concepts/severity) scaling by dose and predisposition. No controlled human studies exist; the current understanding rests on a single 2023 mouse pharmacology study and [structural analogy](https://psychedex.org/concepts/structural-analogy) to psilocybin[2]. ## History #### Discovery The foundation for 4-PrO-DMT lies in a 1963 [Sandoz](https://psychedex.org/resources/r/sandoz) patent by [Albert Hofmann](https://psychedex.org/resources/r/hofmann) and Franz Troxler, which covered a series of 4-position ester [prodrugs](https://psychedex.org/concepts/prodrug) of [psilocin](https://psychedex.org/substances/psilocin) — including [psilacetin](https://psychedex.org/substances/4-aco-dmt)[3]. The propionyl ester was not specifically named in that filing, and no academic attention followed for over five decades. #### Emergence and identification 4-PrO-DMT first surfaced on online research chemical markets in May 2019, sold as an [unscheduled](https://psychedex.org/concepts/unscheduled) alternative to psilocybin alongside other psilocin prodrug analogs[3][2][6]. Swedish drug monitoring authorities identified it as a [new psychoactive substance](https://psychedex.org/concepts/novel-psychoactive-substance) in July 2019, marking its first documented encounter in a national [surveillance](https://psychedex.org/concepts/surveillance) system[3]. #### First pharmacological study The first formal scientific characterization appeared in April 2023, when Glatfelter et al. published [receptor binding](https://psychedex.org/concepts/receptor-binding) profiles, a crystal structure, and behavioral data in mice — a collaboration between CaaMTech, the University of Massachusetts Dartmouth, and the NIDA Intramural Research Program[2]. No clinical trials have been registered as of September 2026, and no controlled human studies are publicly planned. **Culture and lore** The name 4-PrO-DMT follows systematic research [chemical nomenclature](https://psychedex.org/concepts/chemical-nomenclature): "4-PrO" denotes the propionyloxy ester at the 4-position of the [indole](https://psychedex.org/substances/class/chemical/indole) ring, and "[DMT](https://psychedex.org/substances/dmt)" identifies the N,N-dimethyltryptamine [backbone](https://psychedex.org/concepts/scaffold). The alternate designation **O-propionylpsilocin** emphasizes its relationship to [psilocin](https://psychedex.org/substances/psilocin) as the parent phenol. Both names circulate in research chemical communities; neither has entered mainstream recognition. ## Chemistry #### Structure 4-PrO-DMT is built on the [tryptamine](https://psychedex.org/substances/class/chemical/tryptamine) [backbone](https://psychedex.org/concepts/scaffold) — a bicyclic [indole](https://psychedex.org/substances/class/chemical/indole) ring fused to an ethylamine [side chain](https://psychedex.org/concepts/side-chain) — shared by [endogenous](https://psychedex.org/concepts/endogenous) [serotonin](https://psychedex.org/concepts/serotonin) and [N,N-dimethyltryptamine](https://psychedex.org/substances/dmt)[7]. Two [modifications](https://psychedex.org/concepts/modification) define the molecule: the terminal amine carries two methyl groups (N,N-dimethylation), and the 4-position of the indole ring bears a propionyloxy ester — a three-carbon acyl group linked through an oxygen to the ring. This ester bond is the [prodrug](https://psychedex.org/concepts/prodrug) mechanism: [enzymes](https://psychedex.org/concepts/enzyme) cleave it to expose the 4-hydroxyl group of [psilocin](https://psychedex.org/substances/psilocin)[2].
Molecular formulaC₁₅H₂₀N₂O₂
Molecular weight260.33 g/mol
#### Structural relationships 4-PrO-DMT belongs to a homologous series of psilocin 4-acyloxy prodrugs distinguished by acyl chain length. [Psilacetin](https://psychedex.org/substances/4-aco-dmt) carries a two-carbon acetyl group; 4-PrO-DMT extends this by one methylene unit to a three-carbon propionyl group. psilocybin achieves the same prodrug function through a phosphate ester rather than a carboxylate ester[1]. The longer acyl chain is expected to modestly increase [lipophilicity](https://psychedex.org/concepts/lipophilicity) and may influence how quickly the ester is cleaved, though no published data confirm altered [pharmacokinetics](https://psychedex.org/concepts/pharmacokinetics) for 4-PrO-DMT specifically[8]. #### Stereochemistry and physical properties The molecule contains no stereocenters and is achiral[2]. Research-grade material (as the hydrofumarate salt) presents as a white to off-white crystalline solid[9]. The crystal structure was determined by X-ray diffraction and is reported in the primary pharmacology study[2]. No melting point, partition coefficient, or aqueous [solubility](https://psychedex.org/concepts/solubility) at physiological pH has been published. [Stability](https://psychedex.org/concepts/stability) under ambient conditions and [degradation](https://psychedex.org/concepts/degradation) pathways have not been characterized. ## Pharmacology #### Mechanism of action 4-PrO-DMT is a [prodrug](https://psychedex.org/concepts/prodrug). [Plasma](https://psychedex.org/concepts/plasma) and tissue esterases cleave the propionyl ester at the 4-position of the [indole](https://psychedex.org/substances/class/chemical/indole) ring, releasing [psilocin](https://psychedex.org/substances/psilocin) as the pharmacologically [active metabolite](https://psychedex.org/concepts/active-metabolite)[2][10][8]. This parallels how psilocybin is converted to psilocin by phosphatase [enzymes](https://psychedex.org/concepts/enzyme), and how [psilacetin](https://psychedex.org/substances/4-aco-dmt) is converted by the same esterase [hydrolysis](https://psychedex.org/concepts/hydrolysis) pathway[1]. Psilocin produces its [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic) effects primarily through agonism at [5-HT₂A](https://psychedex.org/concepts/5-ht2a) [receptors](https://psychedex.org/concepts/receptor) on cortical [neurons](https://psychedex.org/concepts/neuron). In mice, 4-PrO-DMT [triggers](https://psychedex.org/concepts/trigger) the [head-twitch response](https://psychedex.org/concepts/head-twitch-response) — a standard proxy for psychedelic activity — at doses of 0.3–3 mg/kg ([subcutaneous](https://psychedex.org/concepts/subcutaneous)), and this response is fully blocked by the selective 5-HT₂A [antagonist](https://psychedex.org/concepts/antagonist) M100907[2]. At higher doses (≥3 mg/kg), concurrent [activation](https://psychedex.org/concepts/activation) of [5-HT₁A](https://psychedex.org/concepts/5-ht1a) receptors produces [sedation](https://psychedex.org/effects/sedation) and drops in [body temperature](https://psychedex.org/concepts/body-temperature), which partially suppress the head-twitch response — a pattern consistent with the interplay between excitatory and inhibitory [serotonin](https://psychedex.org/concepts/serotonin) pathways observed across [tryptamine](https://psychedex.org/substances/class/chemical/tryptamine) psychedelics[2][11]. #### Pharmacokinetics No human pharmacokinetic data exist for 4-PrO-DMT. The parameters below are derived from psilocin studies following psilocybin administration and are applicable by [structural analogy](https://psychedex.org/concepts/structural-analogy)[12][13]. The prodrug undergoes hydrolysis by plasma and tissue esterases to yield psilocin[2][10]. The rate at which the propionyl ester is cleaved relative to the acetyl ester of psilacetin or the phosphate ester of psilocybin has not been published. General ester chemistry suggests the propionyl group may hydrolyze more slowly, potentially affecting onset timing — but this remains unconfirmed. Once liberated, psilocin reaches peak [plasma levels](https://psychedex.org/concepts/plasma-concentration) within approximately 2–4 hours of oral dosing, with an oral [bioavailability](https://psychedex.org/concepts/bioavailability) around 50% and an [elimination half-life](https://psychedex.org/concepts/half-life) of 1.5–4 hours[12][13]. Psilocin is cleared primarily through conjugation and oxidative [metabolism](https://psychedex.org/concepts/metabolism); genetic variation in the relevant enzymes does not significantly alter psilocin blood levels[13]. [inferred] These values describe psilocin following psilocybin administration; timing for 4-PrO-DMT may differ because the propionyl ester hydrolysis step adds an unquantified delay. ## Neuroscience #### Where it acts No direct neuroimaging or [electrophysiology](https://psychedex.org/concepts/electrophysiology) data have been published for 4-PrO-DMT. As a [prodrug](https://psychedex.org/concepts/prodrug) of [psilocin](https://psychedex.org/substances/psilocin), its neural effects are inferred from psilocybin research, where the active agent reaching brain [receptors](https://psychedex.org/concepts/receptor) is identical. Psilocin engages [5-HT₂A](https://psychedex.org/concepts/5-ht2a) receptors concentrated on cortical pyramidal [neurons](https://psychedex.org/concepts/neuron), disrupting the brain's [default mode network](https://psychedex.org/concepts/default-mode-network) and loosening thalamocortical gating — changes that underlie the dissolution of ordinary self-boundaries, novel associative thinking, and perceptual distortion[14][15]. PET imaging shows that subjective [intensity](https://psychedex.org/concepts/intensity) tracks directly with [receptor occupancy](https://psychedex.org/concepts/receptor-occupancy), reaching up to 72% at [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic) doses[16]. #### Why it matters Psilocin-class compounds promote structural changes in brain connectivity. [Activation](https://psychedex.org/concepts/activation) of cortical 5-HT₂A receptors stimulates growth-factor [signaling cascades](https://psychedex.org/concepts/signaling-cascade) that increase dendritic branching and the [density](https://psychedex.org/concepts/density) of synaptic connections[15]. These neuroplastic effects are hypothesized to underlie the therapeutic potential of psychedelics — the REBUS model proposes that psychedelics temporarily relax entrenched cognitive patterns, opening a window in which rigid mental habits can be revised[15]. Whether psilocin delivered via 4-PrO-DMT produces identical [neuroplastic changes](https://psychedex.org/concepts/neuroplasticity) has not been specifically tested, but the shared [active metabolite](https://psychedex.org/concepts/active-metabolite) makes this a reasonable expectation. **Open questions** Several unresolved questions are specific to 4-PrO-DMT's prodrug architecture. Does the propionyl ester undergo any [hydrolysis](https://psychedex.org/concepts/hydrolysis) within the brain itself, or is conversion to psilocin complete in peripheral blood? If partial brain hydrolysis occurs, the local rate of psilocin generation could differ from what blood levels suggest. Separately, 4-PrO-DMT binds 5-HT₂B receptors with unexpectedly high [affinity](https://psychedex.org/concepts/affinity) before it is converted to psilocin — whether the intact prodrug molecule engages brain 5-HT₂B receptors during this pre-hydrolysis window, and what neural consequences this might produce, is unknown[2]. ## Subjective Effects The 4-PrO-DMT experience carries the full-spectrum serotonergic [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic) signature. Visual, cognitive, emotional, and somatic dimensions coactivate rather than emerging in isolation, and the qualitative character is shaped more by psychological set and environmental setting than by dose alone. At lower doses, the experience centers on perceptual brightening, gentle introspective shifts, and emotional openness; at higher doses, the architecture of ordinary selfhood destabilizes — [ego dissolution](https://psychedex.org/effects/ego-dissolution) and profound alterations in the sense of time and meaning become defining features. Community reports describe an experience qualitatively indistinguishable from psilocybin or [psilacetin](https://psychedex.org/substances/4-aco-dmt), consistent with all three compounds converging on the same [active metabolite](https://psychedex.org/concepts/active-metabolite)[1]. Some users report a marginally slower onset than psilacetin — a claim unconfirmed by pharmacokinetic data. The overall character aligns with the [tryptamine](https://psychedex.org/substances/class/chemical/tryptamine) psychedelic family: warmer and more inward-turning than [LSD](https://psychedex.org/substances/lsd), with a less electrically stimulating body feel. ## Safety #### Toxicity ##### Acute toxicity No controlled [toxicity](https://psychedex.org/concepts/toxicity) data exist for 4-PrO-DMT, and no human fatalities have been attributed to the compound[3][4]. The [active metabolite](https://psychedex.org/concepts/active-metabolite) [psilocin](https://psychedex.org/substances/psilocin) has a wide margin between active and [lethal doses](https://psychedex.org/concepts/lethal-dose) in [animal models](https://psychedex.org/concepts/animal-model) — the estimated therapeutic index for the psilocybin class is approximately 1,000:1[5][17]. In mice, 4-PrO-DMT produces [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic)-like effects at 0.3–3 mg/kg (subcutaneous), while [sedation](https://psychedex.org/effects/sedation) and temperature drops emerge at 3–30 mg/kg[2]. Transient physiological effects expected at psychoactive doses include [blood pressure](https://psychedex.org/concepts/blood-pressure) [elevation](https://psychedex.org/concepts/elevation), increased [heart rate](https://psychedex.org/concepts/heart-rate), [pupil dilation](https://psychedex.org/effects/pupil-dilation), and [nausea](https://psychedex.org/effects/nausea)[17]. ##### Heart and circulation 4-PrO-DMT binds 5-HT₂B [receptors](https://psychedex.org/concepts/receptor) with unexpectedly high [affinity](https://psychedex.org/concepts/affinity) — substantially stronger at this target than at the primary psychedelic receptor [5-HT₂A](https://psychedex.org/concepts/5-ht2a)[2]. Chronic [activation](https://psychedex.org/concepts/activation) of 5-HT₂B is the established mechanism behind heart valve damage associated with drugs like fenfluramine[18]. Three factors reduce the practical relevance of this finding: 4-PrO-DMT converts to psilocin (which has lower 5-HT₂B affinity) before reaching steady-state exposure; psychedelic use is typically intermittent rather than chronic; and clinical psilocybin studies have demonstrated relative cardiovascular safety[18]. Whether the intact prodrug molecule engages cardiac 5-HT₂B receptors before hydrolysis is complete remains an unresolved safety question. [safety citation needed] #### Psychological risks [Acute psychological distress](https://psychedex.org/concepts/distress) — including [anxiety](https://psychedex.org/effects/anxiety), [confusion](https://psychedex.org/effects/confusion), [paranoia](https://psychedex.org/effects/paranoia), and transient psychotic-like symptoms — can occur at high doses or in unprepared individuals[17]. These reactions are a class effect of [serotonergic psychedelics](https://psychedex.org/concepts/serotonergic-psychedelics), influenced by psychological set, environmental setting, dose, and individual psychiatric [vulnerability](https://psychedex.org/concepts/vulnerability). No substance-specific psychological adverse event data exist for 4-PrO-DMT. [Hallucinogen persisting perception disorder](https://psychedex.org/concepts/hppd) (HPPD) — enduring visual [disturbances](https://psychedex.org/concepts/disturbance) such as [visual snow](https://psychedex.org/effects/visual-haze-noise), halos, and geometric [afterimages](https://psychedex.org/effects/after-images) persisting weeks to months after use — has been documented across the serotonergic psychedelic class[19]. The condition appears rare but may be underreported. Persons with a personal or family history of schizophrenia, schizoaffective [disorder](https://psychedex.org/concepts/disorder), or bipolar I disorder face elevated risk of prolonged or severe [psychotic episodes](https://psychedex.org/concepts/psychotic-episodes) and should not use 4-PrO-DMT[17]. #### Tolerance & dependence **Tolerance** develops rapidly. Repeated 5-HT₂A agonism causes receptor downregulation and functional [desensitization](https://psychedex.org/concepts/receptor-desensitization) within days of consecutive use[20][15]. [Cross-tolerance](https://psychedex.org/concepts/cross-tolerance) is expected with all classical serotonergic psychedelics, including psilocybin, [LSD](https://psychedex.org/substances/lsd), [mescaline](https://psychedex.org/substances/mescaline), and [DMT](https://psychedex.org/substances/dmt). Receptor [sensitivity](https://psychedex.org/concepts/sensitivity) is expected to recover within 1–2 weeks of abstinence. [inferred] **Dependence** does not develop. Serotonergic psychedelics as a class produce neither physical nor psychological dependence[21][22]. No published [case reports](https://psychedex.org/concepts/case-report) describe 4-PrO-DMT [dependence](https://psychedex.org/concepts/dependence), [withdrawal](https://psychedex.org/concepts/withdrawal), or compulsive use patterns. #### Drug interactions The [interaction profile](https://psychedex.org/concepts/drug-interaction) is inferred from psilocin. No substance-specific interaction studies exist. **MAOIs:** The highest-risk combination. [Monoamine oxidase inhibitors](https://psychedex.org/substances/class/pharmacological/monoamine-oxidase-inhibitor) impair [serotonin](https://psychedex.org/concepts/serotonin) [metabolism](https://psychedex.org/concepts/metabolism), creating conditions for [serotonin toxicity](https://psychedex.org/concepts/serotonin-syndrome)[23]. A case report documented a hypertensive emergency and heart attack in a patient taking tranylcypromine and [dextroamphetamine](https://psychedex.org/substances/dextroamphetamine) who consumed [psilocybin mushrooms](https://psychedex.org/substances/psilocybin-mushrooms)[24]. **Lithium:** Analysis of 62 reports of classic psychedelics combined with [lithium](https://psychedex.org/substances/lithium) found that 47% involved [seizures](https://psychedex.org/concepts/seizure) and 39% required medical attention[25]. By contrast, zero of 34 lamotrigine + psychedelic reports involved seizures[25]. **SSRIs:** May blunt the psychedelic effect through competition at serotonin receptors. Blunted effects can lead to compensatory [dose escalation](https://psychedex.org/concepts/dose-escalation)[17]. **Tricyclic antidepressants:** May intensify the experience through serotonin and norepinephrine reuptake inhibition[17]. #### Contraindications The following [contraindications](https://psychedex.org/concepts/contraindication) are derived from the psilocin/psilocybin class. No substance-specific data exist for 4-PrO-DMT. **Absolute:** - Personal or family history of schizophrenia, [psychosis](https://psychedex.org/concepts/psychosis), or bipolar I disorder[17] - Current lithium use[25] - Current MAOI use[23][24] - [Pregnancy](https://psychedex.org/concepts/pregnancy) or breastfeeding[17] **Relative:** - Active heart conditions — transient blood pressure and heart rate increases are class effects; the unresolved 5-HT₂B affinity of 4-PrO-DMT adds additional uncertainty[2][18] - Borderline personality disorder — [emotional lability](https://psychedex.org/effects/emotional-lability) may be intensified[17] - Current tricyclic [antidepressant](https://psychedex.org/substances/class/psychoactive/antidepressant) use — potential enhancement of intensity[17] - Current SSRI use — blunted effects may lead to compensatory dose escalation[17] ## Harm Reduction #### Forms & Identification 4-PrO-DMT circulates almost exclusively as a white to off-white powder or pellet sold through online [research chemical](https://psychedex.org/concepts/novel-psychoactive-substance) vendors. Because the compound is visually indistinguishable from dozens of other [tryptamine](https://psychedex.org/substances/class/chemical/tryptamine) powders — including far more potent substances — [reagent testing](https://psychedex.org/concepts/reagent-kit) alone cannot confirm identity. A positive Ehrlich result (purple reaction) indicates the presence of an [indole](https://psychedex.org/substances/class/chemical/indole) but cannot distinguish 4-PrO-DMT from psilocybin, [psilacetin](https://psychedex.org/substances/4-aco-dmt), [DMT](https://psychedex.org/substances/dmt), or other tryptamines. Quantitative analysis through an analytical testing service is the only reliable method for confirming that the substance and dose match what was sold. Volumetric dosing from calibrated solutions is the most reliable way to measure doses in this [potency](https://psychedex.org/concepts/potency) range — eyeballing powder is unreliable and risks significant over- or under-dosing. #### Set & setting As with all [serotonergic psychedelics](https://psychedex.org/concepts/serotonergic-psychedelics), the quality of the 4-PrO-DMT experience is profoundly shaped by psychological state (set) and physical environment (setting). A calm, familiar, private space with access to nature or comfort objects reduces the likelihood of anxious reactions. Beginning in a positive, rested mental state with clear intentions supports a constructive experience. An experienced, sober companion ("[trip sitter](https://psychedex.org/concepts/sitter)") is strongly recommended, especially for first-time users or higher doses. The sitter's role is to provide calm [reassurance](https://psychedex.org/concepts/reassurance) without directing the experience, and to intervene only if physical safety is at risk. > **Guideline** > > #### Guidelines > > - Test all material with an Ehrlich reagent at minimum. Send a sample to an analytical testing service when possible. > - Use a milligram-precision scale (0.001 g) or prepare a volumetric solution for accurate dosing. > - Start with a threshold or light dose on first use to assess individual [sensitivity](https://psychedex.org/concepts/sensitivity) — especially given the absence of human pharmacokinetic data. > - Eat lightly or fast for 2–3 hours before [ingestion](https://psychedex.org/concepts/ingestion) to reduce [nausea](https://psychedex.org/effects/nausea). > - Clear the schedule for the full duration with no obligations or driving. > - Keep water, light food, and a change of environment available. > - Wait at least 1–2 weeks between sessions to allow full [tolerance](https://psychedex.org/concepts/tolerance) recovery. > **Aftercare** > > #### Aftercare & Integration > > The days following a [psychedelic experience](https://psychedex.org/concepts/psychedelic-experience) often carry a residual openness — emotional sensitivity, novel perspectives, and sometimes [vulnerability](https://psychedex.org/concepts/vulnerability). This window is an opportunity for [integration](https://psychedex.org/concepts/integration): processing the experience through reflection, conversation, or creative [expression](https://psychedex.org/concepts/expression). > > Journaling thoughts and emotions within the first 24–48 hours helps preserve [insights](https://psychedex.org/concepts/insight) before they fade. Talking with a trusted friend or experienced peer can ground difficult material. For experiences that surface unresolved trauma or intense emotion, a [therapist](https://psychedex.org/concepts/therapist) trained in psychedelic integration can provide structured support. > **Recovery** > > #### Recovery & Support > > Serotonergic psychedelics as a class carry low [dependence](https://psychedex.org/concepts/dependence) potential, and compulsive 4-PrO-DMT use is not documented. However, patterns of frequent [psychedelic](https://psychedex.org/substances/class/psychoactive/psychedelic) use can reflect avoidance of underlying psychological difficulties rather than genuine exploration. If psychedelic use is interfering with daily functioning, relationships, or mental health, professional support is warranted. > > Resources include the Fireside Project (62-FIRESIDE / 623-473-7433) for psychedelic [peer support](https://psychedex.org/concepts/peer-support), and local mental health services. > **Emergency** > > #### Emergency Response > > **Recognizing an emergency:** Most difficult psychedelic experiences are distressing but not medically dangerous. Signs that require immediate help include: [self-harm](https://psychedex.org/concepts/self-harm) behavior or expressed intent, complete disconnection from reality with inability to respond to verbal cues, [seizures](https://psychedex.org/concepts/seizure), sustained [chest pain](https://psychedex.org/concepts/chest-pain), or [loss of consciousness](https://psychedex.org/concepts/loss-of-consciousness). > > **Immediate steps:** > > - Call emergency services (911 / 112 / local equivalent) if the person is seizing, unresponsive, expressing intent to harm themselves, or experiencing sustained chest pain. > - Move the person to a quiet, safe space. Remove hazards. > - Speak calmly and simply. Reassure them that the effects are temporary and will pass. > - Do not restrain the person unless they are in immediate danger of harming themselves or others. > - Monitor breathing and [body temperature](https://psychedex.org/concepts/body-temperature) until help arrives. > > **What to tell the dispatcher:** State the substance name (4-PrO-DMT, a tryptamine psychedelic), the approximate amount taken, the time of ingestion, and current symptoms. [Good Samaritan laws](https://psychedex.org/concepts/good-samaritan-law) in many jurisdictions protect callers who seek medical help during a drug-related emergency. ## Legal Status 4-PrO-DMT is not specifically listed in the 1971 United Nations [Convention on Psychotropic Substances](https://psychedex.org/concepts/convention-on-psychotropic-substances). Its legal status varies by jurisdiction and is shaped by its structural relationship to [psilocin](https://psychedex.org/substances/psilocin) — a [Schedule I](https://psychedex.org/concepts/schedule-i) substance internationally — and the varying scope of analog and [novel psychoactive substance](https://psychedex.org/concepts/novel-psychoactive-substance) legislation.
JurisdictionClassificationKey provisions
United StatesNot specifically scheduled (federal)The Federal Analogue Act (21 U.S.C. § 813) may apply if sold for human consumption, treating it as Schedule I by analogy to psilocin[3]. citation needed
United KingdomClass A (Misuse of Drugs Act 1971)Psilocin and its esters are explicitly controlled; maximum penalty life imprisonment for supply[3]
SwedenControlled substanceIdentified as an NPS in July 2019; added to national controlled substance schedules[3]
CanadaNot specifically scheduledNot listed in Controlled Drugs and Substances Act schedules as of 2025[3]
GermanyLegal gray area4-AcO-DMT was added to the NpSG in 2022. Whether the NpSG tryptamine group provisions encompass 4-PrO-DMT is legally debated; no court rulings have been issued[3]
AustraliaSchedule 9 (Prohibited)Controlled as a psilocin analog under TGA Poisons Standard[3]
#### Analog and prodrug considerations 4-PrO-DMT occupies a legally ambiguous position as a [prodrug](https://psychedex.org/concepts/prodrug) of psilocin. In jurisdictions with broad [analog provisions](https://psychedex.org/concepts/analogue-provisions) — the United States, Australia — the structural and pharmacological relationship to psilocin may bring 4-PrO-DMT within the scope of controlled substance legislation even without specific scheduling. In the United Kingdom, psilocin esters are explicitly controlled, resolving this ambiguity. The compound's classification as a novel psychoactive substance in Sweden reflects the broader trend toward blanket legislation covering structural classes rather than individual compounds[26]. ## References [1] Rakoczy RJ, Runge GN, Sen AK, et al. (2024). Pharmacological and behavioural effects of tryptamines present in psilocybin-containing mushrooms. British Journal of Pharmacology. 10.1111/bph.16466 [2] Glatfelter GC, Naeem M, Pham DNK, Golen JA, Chadeayne AR, Manke DR, Baumann MH (2023). Receptor Binding Profiles for Tryptamine Psychedelics and Effects of 4-Propionoxy-N,N-dimethyltryptamine in Mice. ACS Pharmacology & Translational Science. 10.1021/acsptsci.2c00222 [3] Wikipedia contributors (2024). 4-PrO-DMT. https://en.wikipedia.org/wiki/4-PrO-DMT [4] PsychonautWiki contributors (2024). 4-PrO-DMT. https://psychonautwiki.org/wiki/4-PrO-DMT [5] Zhuk O, Jasicka-Misiak I, Poliwoda A, Kazakova A, Godovan VV, Halama M, Wieczorek PP (2015). Research on acute toxicity and the behavioral effects of methanolic extract from psilocybin mushrooms and psilocin in mice. Toxins. 10.3390/toxins7041018 [6] Tittarelli R, Mannocchi G, Pantano F, Romolo FS (2015). Recreational use, analysis and toxicity of tryptamines.. Current neuropharmacology. 10.2174/1570159x13666141210222409 [7] Nichols DE (2018). Chemistry and Structure-Activity Relationships of Psychedelics.. Current Topics in Behavioral Neurosciences. 10.1007/7854_2017_475 [8] Raithatha SA, Hagel JM, Matinkhoo K, Yu L, Press D, Cook SG, et al. (2024). Novel Psilocin Prodrugs with Altered Pharmacological Properties as Candidate Therapies for Treatment-Resistant Anxiety Disorders. Journal of Medicinal Chemistry. 10.1021/acs.jmedchem.3c01225 [9] Cayman Chemical (2024). 4-propanoyloxy DMT product page. https://www.caymanchem.com/product/29951/4-propanoyloxy-dmt [10] Pego AMF, Schoffner M, Sammeta VR, Naeem M, Manke DR, Chadeayne A, Glatfelter GC, Baumann MH, Concheiro-Guisan M (2025). Development and validation of an analytical method for the determination of select 4-position ring-substituted tryptamines in plasma by LC-MS/MS. Journal of Analytical Toxicology. 10.1093/jat/bkaf045 [11] Erkizia-Santamaria I, Alles-Pascual R, Horrillo I, Meana JJ, Ortega JE (2022). Serotonin 5-HT2A, 5-HT2C and 5-HT1A receptor involvement in the acute effects of psilocybin in mice. Biomedicine & Pharmacotherapy. 10.1016/j.biopha.2022.113612 [12] Meshkat S, Al-Shamali H, Perivolaris A, et al. (2025). Pharmacokinetics of Psilocybin: A Systematic Review. Pharmaceutics. 10.3390/pharmaceutics17040411 [13] Thomann J, Kolaczynska KE, Stoeckmann OV, Rudin D, Vizeli P, Hoener MC, Pryce CR, Vollenweider FX, Liechti ME, Duthaler U (2024). In vitro and in vivo metabolism of psilocybin's active metabolite psilocin. Frontiers in Pharmacology. 10.3389/fphar.2024.1391689 [14] Cummins BR, Billac GB, Nichols DE, Nichols CD (2025). 5-HT2A receptors: Pharmacology and functional selectivity. Pharmacological Reviews. 10.1016/j.pharmr.2025.100059 [15] Inserra A, De Gregorio D, Gobbi G (2021). Psychedelics in Psychiatry: Neuroplastic, Immunomodulatory, and Neurotransmitter Mechanisms. Pharmacological Reviews. 10.1124/pharmrev.120.000056 [16] Madsen MK, Fisher PM, Burmester D, et al. (2019). Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels. Neuropsychopharmacology. 10.1038/s41386-019-0324-9 [17] MacCallum CA, Lo LA, Pistawka CA, Deol JK (2022). Therapeutic use of psilocybin: Practical considerations for dosing and administration. Frontiers in Psychiatry. 10.3389/fpsyt.2022.1040217 [18] Wsół A (2023). Cardiovascular safety of psychedelic medicine: current status and future directions. Pharmacological Reports. 10.1007/s43440-023-00539-4 [19] Leistenschneider G, Majic T, Reiche S, Riemer TG (2024). Neuropsychological profiles of patients suffering from hallucinogen persisting perception disorder (HPPD): A comparative analysis with psychedelic-using and non-using controls. Scientific Reports. 10.1038/s41598-024-82216-x [20] Wallach J, Cao AB, Calkins MM, Heim AJ, Lanham JK, et al. (2023). Identification of 5-HT2A receptor signaling pathways associated with psychedelic potential. Nature Communications. 10.1038/s41467-023-44016-1 [21] Ross S (2012). Serotonergic hallucinogens and emerging targets for addiction pharmacotherapies. Psychiatric Clinics of North America. 10.1016/j.psc.2012.04.002 [22] Johnson MW, Griffiths RR, Hendricks PS, Henningfield JE (2018). The abuse potential of medical psilocybin according to the 8 factors of the Controlled Substances Act. Neuropharmacology. 10.1016/j.neuropharm.2018.05.012 [23] Malcolm B, Thomas K (2022). Serotonin toxicity of serotonergic psychedelics. Psychopharmacology. 10.1007/s00213-021-05876-x [24] Barnett BS, Koons CJ, Van den Eynde V, Gillman PK, Bodkin JA (2025). Hypertensive Emergency Secondary to Combining Psilocybin Mushrooms, Extended Release Dextroamphetamine-Amphetamine, and Tranylcypromine. Journal of psychoactive drugs. 10.1080/02791072.2024.2368617 [25] Nayak SM, Gukasyan N, Barrett FS, Erowid E, Erowid F, Griffiths RR (2021). Classic Psychedelic Coadministration with Lithium, but Not Lamotrigine, is Associated with Seizures. Pharmacopsychiatry. 10.1055/a-1524-2794 [26] Greene SL (2022). Tryptamines (Chapter 18 in Novel Psychoactive Substances, 2nd edition). Novel Psychoactive Substances (Dargan P, Wood D, eds.). 10.1016/b978-0-12-818788-3.00014-0