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4-HO-MPT

4-hydroxy-N-methyl-N-propyltryptamine

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4-HO-MPT (4-hydroxy-N-methyl-N-propyltryptamine) — also known as meprocin — is an emerging synthetic psychedelic of the tryptamine class. It is a structural analog of psilocin, distinguished by a longer N-propyl chain and a broader receptor binding profile.[1] 4-HO-MPT is a 5-HT₂A receptor agonist, producing its effects by disrupting default-mode network integrity and cortical sensory filtering.

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Threshold
< 5 mg
Light
10 – 20 mg
Common
20 – 30 mg
Strong
30 – 50 mg
Heavy
50+ mg
12340 h2 h4 h6 h
1Onset
20m–1h2Come-up
1h–2h3Peak
2h–3h4Resolution
1h–2hAftereffects2h–12h
Total5h–7h
Builduprapid
Full reset7 days
Cross-tol.
LSD, psilocin, psilocybin +5 more
Absolute5 entries
Current lithium therapyPersonal or family history of psychotic disordersPregnancyCurrent MAOI therapyConcurrent tramadol use
Relative2 entries
Pre-existing cardiac valvular diseaseCurrent SSRI/SNRI therapy
Dosage varies by body weight, tolerance & metabolism · Not medical advice · Terms

Synthesized in 1981 by Repke, Ferguson, and Bates during systematic research into psilocin analogues,[2] 4-HO-MPT received a single published human trial — Shulgin's 8 mg self-experiment in TiHKAL.[3] It remained obscure until appearing on research chemical markets circa 2016 and in European law enforcement seizures by 2018.[4] No clinical research program has been initiated.

Subjective effects include geometric visual patterns, color enhancement, physical stimulation, and mood elevation. The experience is described as broadly psilocybin-like but with a more energetic body feel and less introspective depth — a lighter, more outward-facing psychedelic state than its parent compound. Vertigo, insomnia, and underwhelming effects at doses others find fully active are reported unsought effects.

4-HO-MPT produces no physical dependence; tolerance resets within seven days via 5-HT₂A downregulation.[5] Its most distinctive risk is potent serotonin₂B receptor affinity — 14-fold stronger than at 5-HT₂A — raising an unresolved cardiac concern, as chronic 5-HT₂B agonism causes valve damage in other drug classes.[1] No controlled toxicity data, clinical trials, or systematic adverse event reporting exist.

History[edit]

Discovery

4-HO-MPT was first synthesized in 1981 by David B. Repke, W.J. Ferguson, and D.K. Bates at Wright State University, as part of a systematic study of psilocin analogues with varied N-alkyl substitution patterns.[2] Alexander Shulgin included it as entry #23 in TiHKAL (1997), though both dose and duration were listed as "unknown" — one of the few entries to carry this designation.[3] His single self-experiment at 8 mg produced mild visual distortion, prominent vertigo, and residual insomnia, but lacked the philosophical depth associated with psilocin.

Research chemical era

4-HO-MPT appeared on online research chemical markets around 2016[6] and was first identified in European law enforcement seizures in 2018.[4] Several jurisdictions have since placed it under controlled substance or novel psychoactive substance legislation. As of 2026, no clinical research program has been initiated for this compound.

Chemistry[edit]

Structural class

4-HO-MPT belongs to the 4-hydroxytryptamine subclass of substituted tryptamines. The parent scaffold is the indole ring system with a 2-aminoethyl side chain at C-3 and a hydroxyl group at C-4. 4-HO-MPT is distinguished by asymmetric N,N-dialkyl substitution: one methyl and one n-propyl group on the terminal nitrogen.

This places it between psilocin (symmetric N,N-dimethyl) and longer-chain homologues such as 4-HO-DPT (symmetric N,N-dipropyl). Its closest structural relative is 4-HO-MiPT, which carries an isopropyl rather than n-propyl chain — a subtle branching difference that alters pharmacological character.

Molecular identity

Molecular formulaC₁₄H₂₀N₂O
Molecular weight232.32 g/mol

The molecule consists of a 4-hydroxyindole nucleus with an ethylamine tether at the 3-position.[8] The terminal nitrogen carries one methyl group (C₁) and one n-propyl group (C₃), giving the molecule 14 carbons, 20 hydrogens, two nitrogens, and one oxygen.

Stereochemistry

4-HO-MPT is achiral — the molecule contains no stereocenters. The n-propyl chain introduces no asymmetric carbon, and no geometric isomerism is present. Stereoisomerism is not a pharmacological consideration.

Physical properties

Melting point (free base)162–163°C
AppearanceWhite to off-white crystalline solid (free base)

The melting point was reported in TiHKAL.[3] No published data exist on aqueous solubility, partition coefficient, or pKa. The 4-hydroxyl group is susceptible to oxidation under aerobic and acidic conditions — a property shared across all 4-hydroxytryptamines — which may degrade samples stored improperly.

The compound is commercially available as the hydrofumarate salt for analytical and research purposes.[9]

Pharmacology[edit]

Mechanism of action

4-HO-MPT produces psychedelic effects through agonism at serotonin 5-HT₂A receptors in the cerebral cortex — the same mechanism established for the 4-hydroxytryptamine class.[10][11] Activation of these receptors on cortical neurons disrupts default-mode network integrity and increases cortical entropy, producing the characteristic alterations in perception, cognition, and self-referential processing.

4-HO-MPT binds 5-HT₂A with moderate affinity for its class.[1] At higher doses, engagement of 5-HT₁A receptors may contribute sedative effects, as demonstrated for structurally similar tryptamines.[12] The compound also engages 5-HT₂B, 5-HT₆, and histamine H₁ receptors at significant concentrations — a broader receptor profile than psilocin.[1]

No functional activity data have been published for 4-HO-MPT specifically. By structural analogy with the class, it is expected to behave as a partial to full agonist at 5-HT₂A.[10][11] The compound induces the head-twitch response in mice, a behavioral marker of 5-HT₂A activation.[9]

Serotonin transporter affinity is low,[1] meaning 4-HO-MPT acts primarily as a receptor agonist without the serotonin-releasing properties of empathogenic tryptamines. This does not eliminate serotonin syndrome risk when combined with serotonin-elevating drugs.

Pharmacokinetics

No controlled human pharmacokinetic study exists for 4-HO-MPT. The oral route is the only documented administration method.

Metabolism has been characterized using pooled human liver cells with high-resolution mass spectrometry.[4] Three phase I metabolites were identified — including products of N-demethylation and N-oxidation — alongside phase II conjugates, with glucuronidation (sugar-group attachment for kidney clearance) being the most abundant metabolic product. This pattern mirrors that of the structural analog 4-HO-MET.[13]

Monoamine oxidase A (MAO-A) is expected to contribute to breakdown of 4-HO-MPT, as established for the tryptamine class broadly.[14] inferred Community-reported timing places onset at 20–60 minutes, peak effects at 2–3 hours, and total duration at 5–7 hours.[15] These values have not been verified in controlled settings.

Neuroscience[edit]

Where it acts

As a serotonin 2A receptor agonist, 4-HO-MPT is expected to reduce connectivity within the default-mode network — the brain system underlying self-referential thought and ego boundaries — while increasing communication between regions that do not normally interact. This shift from modular to globally connected brain activity underlies the perceptual intensification, novel associations, and ego dissolution characteristic of the psychedelic state. The compound's significant histamine H₁ receptor engagement[1] may introduce a sedative or attention-dampening tone not typical of psychedelics with minimal histaminergic activity. inferred

Why it matters

The REBUS (Relaxed Beliefs Under Psychedelics) framework proposes that 5-HT₂A agonism loosens the brain's predictive filtering, allowing raw sensory input to override learned expectations — the neural basis of the psychedelic shift in consciousness. 4-HO-MPT's moderate 5-HT₂A affinity suggests this effect occurs but may require higher doses to reach full intensity compared to more potent ligands.

As a 5-HT₂A agonist, the compound is also predicted to promote structural neuroplasticity — growth of new neural connections — though whether its unusual serotonin₂B engagement modulates this plasticity response differently from psilocin remains unknown. inferred

Subjective Effects[edit]

Summary

The character of 4-HO-MPT is reported as broadly psilocybin-like but distinguished by a more stimulating physical tone and less introspective weight. At lower doses, visual enhancement and mood elevation predominate; at stronger doses, geometric patterning, perceptual distortion, and body load increase substantially. The experience appears sensitive to individual variation — some users report underwhelming effects at doses others find fully psychedelic — and follows the classical psychedelic pattern of strong set-and-setting dependence.

Relative to psilocin, 4-HO-MPT occupies a position of slightly lower potency with a reportedly more energetic body feel. Its closest comparator is 4-HO-MiPT, which differs only in propyl chain branching and produces a similar duration and intensity profile.

Effect Grid

Dose Level:
Description

At 20–30 mg, full psychedelic effects are present. Visual geometry, color enhancement, tracers, and visual drifting become prominent. Internal hallucinations may emerge during eyes-closed states. Time alteration is noticeable — minutes may feel stretched or compressed. Emotional enhancement intensifies, and pattern recognition enhancement colors perception of music, art, and conversation.

The body feel is distinctly stimulating compared to psilocybin mushrooms at equivalent psychedelic intensity. Pupil dilation is pronounced. Nausea may occur during the come-up phase but typically resolves by peak. Spontaneous body sensations are common — waves of warmth, tingling, or bodily pressures.

Full functional impairment should be expected for 5–7 hours. Cognitive and perceptual changes make driving unsafe. Aftereffects including mood shifts and possible insomnia may persist 2–12 hours beyond the main experience.

Modeled from the effect's dose-dependence curve — not per-substance measurements.

Perception(49)likelihood · intensity
Color enhancement
likely
Visual drifting
likely
Color alteration
likely
Geometry
likely
Depth perception distortion
possible
Perspective distortion
possible
Symmetrical texture repetition
possible
Brightness alteration
possible
Music enhancement
possible

Perspective distortion · Symmetrical texture repetition · Brightness alteration · Music enhancement · Visual breathing · Sleep-transition hallucinations · Tracers · After-images · Visual diffraction · Auditory enhancement · Environmental patterning · Light sensitivity · Peripheral vision distortion · Sound sensitivity · Spatial disorientation · Visual haze / noise · Visual morphing · Touch enhancement · Vestibular distortion · Auditory distortion · Auditory misinterpretation · Dreaming enhancement · Ganzfeld effect · Holotropic state · Peripheral misidentification · Proprioceptive distortion · Visual melting · Visual acuity enhancement · Visual acuity suppression · Synesthesia · Visual processing acceleration · Visual magnification · Flashbacks · Internal hallucinations · Object transformations · Environmental orbism / cubism · Object activation · Visual recursion · External hallucinations · Perspective hallucinations · Auditory hallucinations · Visual flipping · Visual scenery slicing · Persisting hallucinations

Visual breathing · Sleep-transition hallucinations · Tracers · After-images · Visual diffraction · Auditory enhancement · Environmental patterning · Light sensitivity · Peripheral vision distortion · Sound sensitivity · Spatial disorientation · Visual haze / noise · Visual morphing · Touch enhancement · Vestibular distortion · Auditory distortion · Auditory misinterpretation · Dreaming enhancement · Ganzfeld effect · Holotropic state · Peripheral misidentification · Proprioceptive distortion · Visual melting · Visual acuity enhancement · Visual acuity suppression · Synesthesia · Visual processing acceleration · Visual magnification · Flashbacks · Internal hallucinations · Object transformations · Environmental orbism / cubism · Object activation · Visual recursion · External hallucinations · Perspective hallucinations · Auditory hallucinations · Visual flipping · Visual scenery slicing · Persisting hallucinations

Body(41)likelihood · intensity
Body scan awareness
likely
Pupil dilation
likely
Body high
likely
Spontaneous body sensations
possible
Heart rate perception changes
possible
Nausea
possible
Motor control impairment!
possible
Temperature dysregulation!
possible
Abnormal heartbeat!
rare

Spontaneous body sensations · Heart rate perception changes · Nausea · Appetite suppression · Stimulation · Tactile euphoria · Tingling / electric sensations · Vibrations / buzzing · Wakefulness · Bodily heaviness · Bodily lightness · Bodily pressures · Body schema distortion · Breathing alteration · Dizziness · Dry mouth · Excessive sweating · Insomnia · Laughter fits · Muscle tension · Physical fatigue · Restlessness · Headache · Muscle relaxation · Sedation · Sexual arousal enhancement · Trembling · Abnormal heartbeat · Diarrhea · Involuntary body movements · Nystagmus (eye wobbles) · Respiratory stimulation · Yawning · Vomiting · Bodily dissociation · Tactile hallucination

Appetite suppression · Stimulation · Tactile euphoria · Tingling / electric sensations · Vibrations / buzzing · Wakefulness · Bodily heaviness · Bodily lightness · Bodily pressures · Body schema distortion · Breathing alteration · Dizziness · Dry mouth · Excessive sweating · Insomnia · Laughter fits · Muscle tension · Physical fatigue · Restlessness · Headache · Muscle relaxation · Sedation · Sexual arousal enhancement · Trembling · Diarrhea · Involuntary body movements · Nystagmus (eye wobbles) · Respiratory stimulation · Yawning · Vomiting · Bodily dissociation · Tactile hallucination

Thinking(41)likelihood · intensity
Aesthetic enhancement
likely
Introspection enhancement
likely
Conceptual thinking
possible
Cognitive euphoria
possible
Novelty enhancement
possible
Cognitive flexibility
possible
Suggestibility enhancement!
possible
Decision impairment!
possible
Delusions!
v.rare

Cognitive euphoria · Novelty enhancement · Cognitive flexibility · Openness enhancement · Thought connectivity · Pattern recognition enhancement · Thought loops · Cognitive impairment · Immersion enhancement · Multiple thought streams · Creativity enhancement · Memory suppression · Focus suppression · Humor enhancement · Increased nature relatedness · Information processing suppression · Memory fragmentation · Synchronicity · Thought acceleration · Thought disorganization · Analysis enhancement · Analysis suppression · Cognitive fatigue · Confusion · Language suppression · Memory replays · Motivation suppression · Information processing enhancement · Cognitive dysphoria · Thought deceleration · Focus enhancement · Language enhancement · Memory enhancement · Motivation enhancement · Delusions · Amnesia

Openness enhancement · Thought connectivity · Pattern recognition enhancement · Thought loops · Cognitive impairment · Immersion enhancement · Multiple thought streams · Creativity enhancement · Memory suppression · Focus suppression · Humor enhancement · Increased nature relatedness · Information processing suppression · Memory fragmentation · Synchronicity · Thought acceleration · Thought disorganization · Analysis enhancement · Analysis suppression · Cognitive fatigue · Confusion · Language suppression · Memory replays · Motivation suppression · Information processing enhancement · Cognitive dysphoria · Thought deceleration · Focus enhancement · Language enhancement · Memory enhancement · Motivation enhancement · Amnesia

Feeling(10)likelihood · intensity
Emotional enhancement
likely
Emotional lability
possible
Euphoria
possible
Empathy enhancement
possible
Simultaneous emotions
possible
Anxiety
possible
Catharsis
possible
Paranoia!
possible
Anxiety suppression
rare

Simultaneous emotions · Anxiety · Catharsis · Anxiety suppression · Dysphoria

Dysphoria

Self(20)likelihood · intensity
Derealization
possible
Emotional susceptibility
possible
Depersonalization
possible
Disinhibition
possible
Social connection
possible
Trust enhancement
possible
Flow state
possible
Sociability enhancement
possible
Self-control suppression!
v.rare

Social connection · Trust enhancement · Flow state · Sociability enhancement · Communication suppression · Communication enhancement · Compulsive behavior reduction · Sociability suppression · Social disconnection · Ego inflation · Boundary dissolution · Cognitive disconnection · Ego dissolution · Identity alteration · Telepathic feelings

Communication suppression · Communication enhancement · Compulsive behavior reduction · Sociability suppression · Social disconnection · Ego inflation · Boundary dissolution · Cognitive disconnection · Ego dissolution · Identity alteration · Telepathic feelings

Time(6)likelihood · intensity
Time alteration
likely
Present-moment absorption
possible
Temporal disorientation
possible
Deja vu
possible
Jamais vu
rare
Time cessation
v.rare

Time cessation

Transpersonal(10)likelihood · intensity
Unity and interconnectedness
possible
Existential realization
rare
Noetic insight
rare
Non-dual awareness
v.rare
Transpersonal feelings
v.rare
Transpersonal visions
v.rare
Entity contact
v.rare
Transpersonal memory access
v.rare
Death-rebirth sequence
v.rare

Transpersonal visions · Entity contact · Transpersonal memory access · Death-rebirth sequence · Voidness

Voidness

Awareness(7)likelihood · intensity
Personal insight
possible
Lucid dreaming enhancement
possible
Mindfulness enhancement
possible
Cognitive dissonance
possible
Lucidity enhancement
possible
Reality testing impairment!
rare
Recursive awareness
rare

Lucidity enhancement · Recursive awareness

Likelihood: how common this effect is at the selected dose level.This effect has safety implications — review before use.

Timeline

Safety[edit]

Harm
Acute toxicity
Low
Chronic toxicity
Moderate
Withdrawal
None
Tolerance buildup
rapid
Tolerance reset
7 days
Dependence
Physical
None
Psychological
Negligible
Compulsive redosing
Negligible
Dose escalation
Negligible
Cross-tol.
LSD · psilocin · psilo
Risk Shape
TOXPHYPSYWDRREDTOL

Toxicity

No lethal dose has been established for 4-HO-MPT in any species. No formal toxicity assessment, safety evaluation, or systematic adverse event surveillance has been published. No fatalities attributed to 4-HO-MPT appear in the published literature or accessible case report databases.

Cardiovascular concerns: 5-HT₂B agonism

4-HO-MPT exhibits exceptionally potent serotonin₂B receptor affinity — its highest-affinity binding target, approximately 14-fold stronger than at the primary psychedelic target 5-HT₂A.[1] Prolonged 5-HT₂B agonism is the established mechanism underlying heart valve damage caused by fenfluramine, ergotamine derivatives, and pergolide. While valve damage in those contexts required chronic daily exposure over months to years, no data exist to characterize the cardiac safety of 4-HO-MPT at any frequency of use.

This represents a safety-critical data gap. No heart imaging, no animal cardiac tissue analysis, and no monitoring of cardiac outcomes among users has been conducted. safety citation needed

Acute toxicity

No published case reports of 4-HO-MPT overdose or emergency presentations were identified. Class-level acute risks for 4-hydroxytryptamines include serotonin syndrome (particularly in combination with serotonin-elevating drugs), rapid heart rate, elevated blood pressure, and dangerously high body temperature at very high doses.[16]

Psychological risks

No 4-HO-MPT-specific psychological adverse event data exist. Class-level risks for serotonergic psychedelics apply:

  • Acute psychological distress — anxiety, paranoia, and thought loops are common at strong doses across all classical psychedelics. Limited user reports for 4-HO-MPT do not suggest unusual psychological volatility, but the evidence base is too thin to draw reliable conclusions.
  • HPPD (Hallucinogen Persisting Perception Disorder) — documented for psilocin and other serotonergic psychedelics.[17] Class-level risk applies.
  • Psychosis precipitation — a theoretical risk in individuals with personal or family history of psychotic disorders. No 4-HO-MPT-specific cases reported.
  • Depersonalization/derealization — transient experiences are common during acute effects; persistent disorders are rare but documented for the class.

Tolerance and dependence

4-HO-MPT does not produce physical dependence. Classical psychedelics as a class show no withdrawal, no compulsive dose escalation, and no reinforcement in animal self-administration studies.[16]

Tolerance develops almost immediately after ingestion through 5-HT₂A downregulation.[5] Full sensitivity returns within approximately 7 days. Cross-tolerance exists with all serotonergic psychedelics acting through 5-HT₂A, including LSD, Psilocin, and DMT.[5]

Drug interactions

Serotonin syndrome risk

The primary pharmacological danger of combining 4-HO-MPT with other drugs is serotonin syndrome. Although 4-HO-MPT has low SERT affinity, its potent post-synaptic serotonin receptor agonism creates additive serotonergic load when combined with drugs that increase synaptic serotonin.

Tramadol combines weak serotonin reuptake inhibitor with opioid effects and is classified as a dangerous interaction.[18]

MAO inhibitors (including harmine, harmaline from Peganum harmala, phenelzine, tranylcypromine) represent a dangerous interaction. MAO-A is expected to be a primary breakdown pathway for 4-HO-MPT;[14] inhibiting it would dramatically amplify and prolong effects while increasing serotonin syndrome risk. inferred

SSRIs and SNRIs create serotonin syndrome risk through mechanism overlap — elevated synaptic serotonin combined with potent post-synaptic agonism. SSRIs may also reduce subjective psychedelic effects through chronic 5-HT₂A downregulation.

Seizure threshold interactions

Lithium combined with serotonergic psychedelics is associated with increased seizure risk. The mechanism is incompletely understood. citation needed

Cannabis

The interaction with cannabis remains uncharacterized. Community reports from other psychedelics suggest cannabis intensifies anxiety, perceptual effects, and paranoia during the peak.

Contraindications

No substance-specific contraindication data exist. Class-level contraindications for serotonergic psychedelics apply:

  • Personal or family history of psychotic disorders (absolute) — 5-HT₂A agonists may trigger or worsen psychosis in predisposed individuals
  • Current MAOI therapy (absolute) — serotonin syndrome risk; MAO-A inhibition dramatically amplifies tryptamine effects
  • Current SSRI/SNRI therapy (relative) — serotonin syndrome risk; may also reduce psychedelic effects
  • Current lithium therapy (absolute) — increased seizure risk with serotonergic psychedelics
  • Pre-existing heart valve disease (relative, specific to 4-HO-MPT) — the potent 5-HT₂B affinity[1] warrants particular caution, though no clinical evidence exists for 4-HO-MPT-specific cardiac harm
  • Pregnancy (absolute) — no safety data; 5-HT₂B is involved in cardiac development; precautionary exclusion

Harm Reduction[edit]

Forms & Identification

Reagent ResultsNot recorded+ add reagent results
AppearanceNot recorded+ add appearance
Red FlagsNot recorded+ add red flags

4-HO-MPT powder is visually indistinguishable from dozens of other white crystalline tryptamines. Given the compound's obscurity, the risk of receiving a mislabeled or substituted product is significant. Reagent testing provides only presumptive identification — a Marquis or Ehrlich result consistent with a tryptamine does not confirm which tryptamine is present.

Quantitative analysis via a drug checking service is the only reliable method of confirming identity and purity. Because 4-HO-MPT is active in the low-milligram range, even small purity variations meaningfully affect dosing.

Guidelines

  • Test every batch with at minimum an Ehrlich reagent; quantitative analysis through a drug checking service is strongly preferred
  • Use a milligram-precision analytical balance — volumetric estimation and "eyeballing" are unreliable at this dose range
  • Start with a low dose if unfamiliar with the compound or batch, as individual sensitivity varies considerably
  • Eat lightly 2–3 hours before dosing to reduce nausea risk
  • Have a sober, trusted companion present, particularly for first experiences or higher doses
  • Prepare the environment: comfortable seating, water, blankets, calming music, and a way to change rooms if the space becomes uncomfortable
  • Do not redose during the experience — 5-HT₂A tolerance develops rapidly and additional doses add duration and adverse effects more than intensity

Set & Setting

4-HO-MPT follows the classical psychedelic pattern of strong sensitivity to mindset and environment. A calm, familiar setting with a trusted sober companion significantly reduces the risk of acute psychological distress. First experiences should be undertaken in a safe, private environment with no obligations for the remainder of the day.

The experience may leave residual stimulation and insomnia; scheduling accordingly — with a full free day and an unhurried evening — reduces downstream stress.

Aftercare & integration. The hours following a 4-HO-MPT experience may include residual stimulation and difficulty sleeping. Gentle activity, hydration, and a light meal support physical recovery. Avoid caffeine or other stimulants if insomnia is present.

Psychedelic experiences can surface unfamiliar emotions or perspectives. Journaling, conversation with a trusted person, or structured integration practices help process the content of the experience. If distressing thoughts or perceptual changes persist beyond 48 hours, consult a mental health professional experienced with psychedelic integration.

Recovery & Support

Classical psychedelics including 4-HO-MPT carry low risk of physical dependence, and compulsive use is self-limiting due to rapid tolerance. However, psychological patterns of repeated use — using psychedelics to escape rather than explore — can develop.

If psychedelic use is causing distress, interfering with daily life, or being used to avoid addressing mental health concerns, support is available through the Fireside Project (62-FIRESIDE), MAPS integration list, and local psychedelic integration circles. General substance use support is available through SAMHSA's National Helpline (1-800-662-4357).

Recovery resources, crisis lines, and support pathways → View all

Emergency Response

Recognizing an emergency: Most difficult 4-HO-MPT experiences involve anxiety, confusion, and perceptual overwhelm — uncomfortable but not medically dangerous. Seek emergency help if any of the following occur: self-harm behavior or expressed intent, complete loss of contact with reality, seizure, chest pain, or dangerously high body temperature (skin hot to the touch with no cooling response).

Immediate steps:

  • 1. Move the person to a calm, quiet space and reduce stimulation
  • 2. Stay with them and speak in a calm, grounding voice
  • 3. Do not restrain unless there is immediate danger of self-harm
  • 4. If unconscious, place in the recovery position (on their side, airway clear)
  • 5. Call emergency services if any red-flag symptoms appear or if the situation is not improving

What to tell the dispatcher: State the substance name (4-HO-MPT, a synthetic tryptamine), the amount taken if known, the time of ingestion, and current symptoms. Good Samaritan laws in many jurisdictions protect people who call for help during a drug emergency.

references

  1. [1] 
    ^abcdefghGlatfelter 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 doi:10.1021/acsptsci.2c00222
  2. [2] 
    ^abRepke (1981) Psilocin analogs II. Synthesis of 3-[2-(dialkylamino)ethyl]-, 3-[2-(N-methyl-N-alkylamino)ethyl]-, and 3-[2-(cycloalkylamino)ethyl]indol-4-ols
  3. [3] 
    ^abcShulgin (1997) TiHKAL: Tryptamines I Have Known and Loved
  4. [4] 
    ^abcCarlier J, Malaca S, Huestis MA, Tagliabracci A, Tini A, Busardò FP (2022) Biomarkers of 4-hydroxy-N,N-methylpropyltryptamine (4-OH-MPT) intake identified from human hepatocyte incubations — Expert Opinion on Drug Metabolism & Toxicology doi:10.1080/17425255.2022.2166826
  5. [5] 
    ^abcde la Fuente Revenga M, Jaster AM, McGinn J, Silva G, Saha S, Gonzalez-Maeso J (2022) Tolerance and Cross-Tolerance among Psychedelic and Nonpsychedelic 5-HT2A Receptor Agonists in Mice — ACS Chemical Neuroscience doi:10.1021/acschemneuro.2c00170
  6. [6] 
    ^Erowid (2016) 4-HO-MPT — Erowid vault Link