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psx:substance/2c-h/issue/emergency@3f0909c25c71

issue2026-09-04recordsuperseded

derived from · upstream

feeds · downstream

none recorded

Closure of psx:substance/2c-h/issue/emergency@3f0909c25c71: 43 upstream, 74 downstream.

psx:substance/2c-h/issue/emergency@3f0909c25c71
├─ derived_from  version/1  Revision 1
├─ invalidated_by  issue/emergency@c15c760aabf6  Issued emergency
  ├─ used  src/url:e8329dd4b64e4d05  2C-H — Psychedelic Science Review
  ├─ used  src/url:69f8f06ae20edef6  PiHKAL: Phenethylamines I Have Known and Loved
  ├─ used  src/doi:10.1021/acsptsci.0c00063  Structure-Activity Relationship Analysis of Psychedelics in a Rat Model of Asthma Reveals the Anti-Inflammatory Pharmacophore
  ├─ used  src/doi:10.1002/dta.2494  Interactions of phenethylamine-derived psychoactive substances of the 2C-series with human monoamine oxidases
  ├─ used  src/doi:10.1007/s13181-013-0295-x  2C or Not 2C: Phenethylamine Designer Drug Review
  ├─ used  src/url:1adf76812e485a96  2C-H — Wikipedia
  ├─ used  src/pmid:21105535  Role of 3,4-dimethoxyphenethylamine in schizophrenia
  ├─ used  src/doi:10.16889/isomerdesign-1  PeakAL: Protons I Have Known and Loved — NMR spectra of psychedelic phenylethanamines including TMA-2
  ├─ used  src/doi:10.1021/acschemneuro.0c00129  Investigation of the 2,5-Dimethoxy Motif in Phenethylamine Serotonin 2A Receptor Agonists
  ├─ used  src/url:470e25442add4d1b  NIST WebBook — 2,5-Dimethoxyphenethylamine (CAS 3600-86-0)
  ├─ used  src/doi:10.1007/s00204-020-02693-7  Designer drugs: mechanism of action and adverse effects
  ├─ used  src/doi:10.1016/j.neuropharm.2018.02.033  Comparative neuropharmacology of N-(2-methoxybenzyl)-2,5-dimethoxyphenethylamine (NBOMe) hallucinogens and their 2C counterparts in male rats
  ├─ used  src/doi:10.1021/acsptsci.3c00297  Serotonin-2 Receptor Agonists Produce Anti-inflammatory Effects through Functionally Selective Mechanisms That Involve the Suppression of Disease-Induced Arginase 1 Expression
  ├─ used  src/pmid:20540700  Metabolism of designer drugs of abuse: an updated review
  ├─ used  src/doi:10.1371/journal.pone.0009019  Psychedelics and the human receptorome
  ├─ used  src/doi:10.1038/s41467-023-44016-1  Identification of 5-HT2A receptor signaling pathways associated with psychedelic potential
  ├─ used  src/pmid:25416380  Serotonin 5-HT2 receptor activation prevents allergic asthma in a mouse model
  ├─ used  src/doi:10.1016/j.lfs.2019.116790  5-HT2 receptor activation alleviates airway inflammation and structural remodeling in a chronic mouse asthma model
  ├─ used  src/doi:10.3390/jox14020044  Mechanistic Insights into the Neurotoxicity of 2,5-Dimethoxyphenethylamines (2C) and Corresponding N-(2-methoxybenzyl)phenethylamine (NBOMe) Drugs
  ├─ used  src/doi:10.1021/acschemneuro.2c00170  Tolerance and Cross-Tolerance among Psychedelic and Nonpsychedelic 5-HT2A Receptor Agonists in Mice
  ├─ used  src/doi:10.1007/s00482-015-1512-0  Serotonin syndrome and pain medication: What is relevant for practice?
  ├─ used  src/doi:10.1177/0897190013504957  Serotonin syndrome: is it a reason to avoid the use of tramadol with antidepressants?
  ├─ derived_from  gen/0e8b907b-7090-46d3-b35a-ab6e67595616  Generation — pipeline-v5
  ├─ generated_by  pub/b2fa429b-6059-4ab7-a7ae-ee4025bd2653  Publication — backfill
    ├─ used  search/4df2d15e-719a-452c-b1fe-6a373a5c9c9f  Searched PubMed for "2C-H 2,5-dimethoxyphenethylamine pharmacology"
    ├─ used  search/245753a1-e618-4421-83b3-e221bb3ba70e  Searched PubMed for "DMPEA dimethoxyphenethylamine psychedelic schizophrenia"
    ├─ used  search/908279cf-fa06-4bcc-b3d0-85bc596a6951  Searched PubChem for "2,5-dimethoxyphenethylamine"
    ├─ used  search/c47c9d88-37d7-4b65-883f-ef50e3e2acd1  Searched OpenAlex for "2,5-dimethoxyphenethylamine DMPEA pharmacology psychedelic"
    ├─ used  search/4f069f16-fff8-40b1-acc9-50a986615a5c  Searched OpenAlex for "phenethylamine psychedelics 2C series serotonin receptor binding affinity"
    ├─ used  search/073d29f1-7c84-45b7-9223-6c9a50d5c7f1  Searched OpenAlex for "3,4-dimethoxyphenethylamine pink spot schizophrenia DMPEA urine"
    ├─ used  search/1b6eacee-3099-4c43-ac10-19e2c2f13112  Searched PubMed for "phenethylamine receptor binding affinity 5-HT2A structure activity relationship psychedelic"
    ├─ used  search/c628fb8e-423f-4f5b-abb2-64e536f219f3  Searched ClinicalTrials.gov for "2C-H 2,5-dimethoxyphenethylamine"
    ├─ used  search/152abb8a-9c79-4748-9da0-690e39cb3eff  Searched PubMed for "PMID 30188017"
    ├─ used  search/e4a5269e-4bf9-4a2f-a2ae-bab7ca7d2e49  Searched WebSearch for "2C-H PiHKAL Shulgin 'probably inactive' MAO dose unknown synthesis"
    ├─ used  search/f97feafc-c750-43dd-bb41-b941a4cd271c  Searched WebSearch for "2C-H phenethylamine legal status UK USA Australia scheduling controlled substance"
    ├─ used  search/c2edd909-15d6-4f94-86e9-87f40451746d  Searched Psychedelic Review / WebFetch for "2C-H compound information"
    ├─ used  search/965ebf8c-3528-428c-a873-0cc46e445ce2  Searched WebSearch for "Buck 1932 first synthesis 2,5-dimethoxyphenethylamine"
    ├─ used  search/85e37bff-9809-46ec-b6a2-87a92aab8200  Searched PubMed for "PMID 33860179"
    ├─ used  search/6b8ccf9a-439a-4568-95e9-f4b43b54c01a  Searched PubMed for "tramadol serotonin toxicity syndrome serotonergic drugs combination risk"
    ├─ used  search/a3f3ca1d-cdac-4342-a617-456db5e95b97  Searched NIST WebBook WebFetch for "2,5-dimethoxyphenethylamine physical properties"
    └─ used  search/98b99bd1-2226-4c1f-879c-74f9e85dbd28  Searched WebSearch for "2C-H legal status Wikipedia"
  ├─ derived_from  issue/notice@64878b43a1d2  Issued notice
  ├─ derived_from  issue/info_card@c977c8678c50  Issued info_card
  ├─ derived_from  issue/notice@53ffc98bc5c1  Issued notice
  ├─ derived_from  issue/info_card@f8f8bf78a780  Issued info_card
    ├─ used  claim/a6010b20-4838-49d6-8560-57153cb809cf  Claim in summary — supported
    ├─ used  claim/c373d4a3-0382-4181-88bb-68e3db3aa8df  Claim in pharmacology — supported
    ├─ used  claim/f98dc75d-231a-4cef-b204-b60839cfd83d  Claim in pharmacology — supported
    ├─ used  claim/60a9e724-daab-4bdd-be56-79a04a12a913  Claim in history — supported
    ├─ used  claim/f03cae46-9393-4f33-8d84-7bd452924b81  Claim in receptor-pharmacology — supported
    ├─ used  claim/2d4233f7-576a-4f6d-bd10-1800099dcf01  Claim in clinical-evidence — supported
    ├─ used  claim/c9008a55-e4b8-4e79-838a-823cb3a86bfe  Claim in comparative-pharmacology — supported
    ├─ used  claim/54670372-b3d7-4270-b7a4-73ac493b65e2  Claim in neuroscience — supported
    ├─ used  claim/304e8a3e-aeb0-45c8-a97a-46ebb675d086  Claim in neuroscience — supported
    ├─ used  claim/13a9c51b-a16b-4716-acd1-6d5e28063b61  Claim in summary — supported
    ├─ used  claim/f4f1d823-a9e4-4d99-912c-d1fb7775a480  Claim in pharmacology — supported
    ├─ used  claim/9b4e68f8-8710-465e-9534-165341ce758a  Claim in pharmacology — inconclusive  working
    ├─ used  claim/43b41d96-fad3-495c-99d9-44633f853eba  Claim in pharmacology — inconclusive  working
    ├─ used  claim/e6243726-56d5-4033-8149-dfab22ceeaf3  Claim in pharmacology — supported
    ├─ used  claim/d79de452-abd2-4c7c-8b98-07bf78002b11  Claim in pharmacology — inconclusive  working
    ├─ used  claim/5e35aafe-4eb1-411d-89cb-c5b58976ce42  Claim in pharmacology — inconclusive  working
    ├─ used  claim/66c32af3-f6c5-4f54-abb1-33c174234420  Claim in safety — supported
    ├─ used  claim/5b1b8a06-a8ec-4f2e-9ed5-0ee3b4c6af17  Claim in safety — supported
    ├─ used  claim/d1a98707-a804-4eeb-8560-8bc6104b72b1  Claim in safety — supported
    ├─ used  claim/6bc5b0a8-188a-4d5c-8d6e-33e8f50f914d  Claim in receptor-pharmacology — supported
    ├─ used  claim/e7b2709d-e4ce-4de0-a632-297b1b243d26  Claim in receptor-pharmacology — inconclusive  working
    ├─ used  claim/efda5115-b11b-40cd-bbd7-0c33714397ae  Claim in pharmacokinetic-detail — inconclusive  working
    ├─ used  claim/89285d5b-4546-4953-8163-2de4b9148817  Claim in comparative-pharmacology — supported
    ├─ used  claim/aaff4e88-b6eb-41ee-82e5-44adf879ecea  Claim in summary — inconclusive  working
    ├─ used  claim/062d0877-aab6-4f90-b257-46aa510b14cb  Claim in pharmacology — inconclusive  working
    ├─ used  claim/60b4c09a-dac8-4e76-a0da-aa2b8b373f0c  Claim in safety — inconclusive  working
    ├─ used  claim/692be30e-9da9-4db5-ba1b-563d104bcb5e  Claim in safety — supported
    ├─ used  claim/1d5a91f3-be75-43b4-8dfb-8e24d36dc85d  Claim in safety — partially_supported
    ├─ used  claim/85ee7f99-8dd2-453a-87ba-ae40f27c00e4  Claim in safety — inconclusive  working
    ├─ used  claim/0f323aa4-ec9e-49a6-9872-14a7c84e21c4  Claim in neuroscience — inconclusive  working
    ├─ used  claim/e9fa6673-7a47-4a3a-8707-56b51b499984  Claim in history — inconclusive  working
    ├─ used  claim/723f9f26-b750-4d6c-88a1-befdad6a0cd0  Claim in history — supported
    ├─ used  claim/87495e08-c51d-4855-897d-a2f9c798ea63  Claim in pharmacology — inconclusive  working
    ├─ used  claim/bbe630d1-626f-4b2d-b656-ee5ab11f91d5  Claim in pharmacology — not_supported  working
    ├─ used  claim/7a6e36c1-ee7f-400a-914d-1d0b592ffa4d  Claim in pharmacology — partially_supported
    ├─ used  claim/f5818da1-1028-46fb-bf7e-84dfc2a066a2  Claim in chemistry — supported
    ├─ used  claim/7b4f8826-a4bf-480e-b38a-0d6110e9017c  Claim in comparative-pharmacology — not_supported  working
    ├─ used  claim/f18cef5e-9bf4-4d9a-9ac8-9fffed355666  Claim in pharmacology — supported
    ├─ used  claim/86be094a-724e-4d6c-8f15-bb6ebaa3a5e0  Claim in neuroscience — inconclusive  working
    ├─ used  claim/0410171f-38e3-4a8c-abe6-5c149cf32a20  Claim in pharmacology — supported
    ├─ used  claim/908602f6-d815-4dbc-83da-3c9b0e3cb2d1  Claim in pharmacology — supported
    ├─ used  claim/6d045646-b3be-41aa-92f9-9725645f7603  Claim in receptor-pharmacology — supported
    ├─ used  claim/9b91fd0e-dcdd-44e9-83d7-85d5c4f457f1  Claim in clinical-evidence — supported
    ├─ used  claim/03ac01b2-928c-4b36-99e3-55df040bbe64  Claim in neuroscience — supported
    ├─ used  claim/85deacbe-593c-4745-9246-6d6e6c0d3383  Claim in pharmacology — inconclusive  working
    ├─ used  claim/aa89ee61-7a20-4a50-ac78-d2503f08d2f2  Claim in pharmacokinetic-detail — inconclusive  working
    ├─ used  claim/abaf87e0-55e6-4299-9f74-12b362942762  Claim in pharmacokinetic-detail — inconclusive  working
    ├─ used  claim/44c6c37f-02c2-4a47-9018-033e3a64984a  Claim in receptor-pharmacology — supported
    ├─ used  claim/0d1e867b-d4db-4eb2-b615-c89f80b508ba  Claim in receptor-pharmacology — inconclusive  working
    ├─ used  claim/fda979cc-9d97-47d1-929a-6d3281b186bb  Claim in neuroscience — inconclusive  working
    ├─ used  claim/17318187-d7d9-4440-87c2-4c0df1cd48b4  Claim in neuroscience — supported
    ├─ used  claim/2f936066-4f32-4b50-b801-4a3d48044aeb  Claim in clinical-evidence — supported
    ├─ used  claim/a6637b02-e370-4817-bf60-2d44cfca7cab  Claim in clinical-evidence — supported
    ├─ used  claim/50cdef61-ffdc-4b01-bb3a-66cfef2d0508  Claim in safety — supported
    ├─ used  claim/f4ed40c6-a054-4ebf-aaa9-fa5ef9d7cc0e  Claim in comparative-pharmacology — supported
    ├─ used  claim/8a530c38-0450-421f-a853-e36a0ba59c99  Claim in safety — partially_supported
    ├─ used  claim/f4ac3c49-e30d-41a4-838b-9c1a0d04ce20  Claim in safety — supported
    ├─ used  claim/3f874b45-0396-46c2-89e9-f40b1b9a4010  Claim in safety — supported
    ├─ used  claim/79c25fc7-8e5c-472b-8ea2-0374d022262b  Claim in safety — supported
    ├─ used  claim/6ee656ac-8d35-4c82-9221-fce515915393  Claim in safety — supported
      ├─ informed_by  section/summary.full@1
      ├─ informed_by  section/pharmacology.full@1
      ├─ informed_by  section/history.full@1
      ├─ informed_by  section/receptor-pharmacology.full@1
      ├─ informed_by  section/clinical-evidence.full@1
      ├─ informed_by  section/comparative-pharmacology.full@1
      ├─ informed_by  section/neuroscience.full@1
      ├─ informed_by  section/safety.full@1
      ├─ informed_by  section/pharmacokinetic-detail.full@1
      └─ informed_by  section/chemistry.full@1

indented by distance from this node, not by parentage

1Provenance card

the boundary, as counts

Sources

2215 with DOI

2 strong · 14 moderate · 6 weak

Compilations

12026-05-11T02:12:20.405Z

pipeline-v5 · prompt hash not recorded — run predates 2026-09

Decisions

22last ruled 2026-06-04

0 awaiting a ruling

Issued documents

62026-10-19T20:29:22.001Z

notice · info card · emergency

Searches

172 with no results

queries and counts on the build

Claims checked

6039 supported

39 supported · 21 not

Correspondence

0received

consent field ships in Phase 4

Edges

199

derivations recorded for this entity

Complete over 22 sources, 1 compilation, and 22 decisions.Not here: the private journal (never).Working material — drafts, discards, unsupported claims — is listed below and readable on the working page.Cite: psychedex.org/substances/2c-h/archive

2Build

one panel per compilation run

generation run 2026-05-11

63 min completedmodel pipeline-v5plan not recordedrun/5cc929cf…

Selection

results seen86
selected by the model25
consumed as sources22

Verification

claims checked60
supported36
partially supported3
not supported2
inconclusive19
  • record
  • seen / partial
  • working

The model's own caveats

5 further caveats recorded as free text — readable on the working page

Reproduce

inputs
22 source keys (listed under Sources)
plan
not recorded — template version, prompt hash and git SHA are written from 2026-09 onward
model
pipeline-v5
streams
none — agent transcripts are persisted from 2026-09 onward
17 searches — query, source, results, what was kept and why
17 searches for this run
#sourcequeryseenkeptrationale
1OpenAlex3,4-dimethoxyphenethylamine pink spot schizophrenia DMPEA urine31Historical context for DMPEA naming; important to flag that 3,4-DMPEA != 2C-H
2PubMedphenethylamine receptor binding affinity 5-HT2A structure activity relationship psychedelic153Marcher-Rørsted 2020 directly investigates the 2,5-DMPEA scaffold (which is 2C-H), making it the most relevant receptor pharmacology paper
3PubMed · absenceDMPEA dimethoxyphenethylamine psychedelic schizophrenia0——
4PubMed · absence2C-H 2,5-dimethoxyphenethylamine pharmacology0——
5OpenAlexphenethylamine psychedelics 2C series serotonin receptor binding affinity104Landmark papers covering 2C phenethylamine pharmacology and class effects
6PubChem2,5-dimethoxyphenethylamine11Primary chemical identity data for 2C-H
7OpenAlex2,5-dimethoxyphenethylamine DMPEA pharmacology psychedelic21NMR data for 2C series compounds including potentially 2C-H
8ClinicalTrials.gov2C-H 2,5-dimethoxyphenethylamine10—
9PubMedPMID 3018801711KEY PAPER: directly tested 2C-H for MAO-B inhibition, providing mechanistic explanation for Shulgin's observation that 2C-H is probably orally inactive
10WebSearchBuck 1932 first synthesis 2,5-dimethoxyphenethylamine101Historical synthesis reference
11Psychedelic Review / WebFetch2C-H compound information13Key pharmacological data including receptor binding affinities
12WebSearch2C-H PiHKAL Shulgin 'probably inactive' MAO dose unknown synthesis101Primary source for Shulgin's historical notes on 2C-H
13WebSearch2C-H phenethylamine legal status UK USA Australia scheduling controlled substance103Legal status data
14PubMedtramadol serotonin toxicity syndrome serotonergic drugs combination risk102Evidence base for dangerous tramadol interaction listed in brief
15PubMedPMID 3386017911Primary paper establishing 2C-H as anti-inflammatory pharmacophore - most pharmacologically significant finding for this substance
16WebSearch2C-H legal status Wikipedia101Legal status research for all major jurisdictions
17NIST WebBook WebFetch2,5-dimethoxyphenethylamine physical properties12Government-grade verified chemical identifiers
60 claims by section — every cited sentence, checked against its source
pharmacology16 · 8 ok
  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • Claim in pharmacology — not_supportednot supportedworking →

  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • For the 2C series as a class, psychedelic effects are mediated primarily through 5-HT₂A receptor partial agonismsupported

    5-HT2A/2C receptors mediate alterations of perception and cognition induced by serotonergic psychedelics. s00204-020-02693-7

  • For the 2C series as a class, psychedelic effects are mediated primarily through 5-HT₂A receptor partial agonismsupported

    2,5-Dimethoxyphenethylamines (2C compounds) are 5-HT2A/2C receptor agonists that induce hallucinogenic effects. j.neuropharm.2018.02.033

  • Marcher-Rørsted et al. (2020) demonstrated that removing either methoxy group produces modest in vitro affinity reductions but significant attenuation of in vivo head-twitch response in mice, confirming that both methoxy groups contribute to receptor binding geometry while the 4-substituent drives functional potency.partially supported

    Elimination of either the 2- or 5-methoxy group leads to modest drop in binding affinity... Trend not mirrored in vivo — removal of either methoxy group resulted in significant reduction in head-twitch response in mice. acschemneuro.0c00129

  • Wagmann et al. (2019) screened 12 2C-series compounds and 5 FLY analogues against human MAO-A and MAO-B using in vitro heterologously expressed enzyme assays with HILIC-HR-MS/MS analysis. 2C-H was identified as the most potent MAO-B inhibitor in the 2C series, with an IC₅₀ of 1.7 µM (range across nine active compounds: 1.7–180 µM)supported

    17 drugs tested: 12 2Cs... and five FLY analogs. 2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. dta.2494

  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • Second, the MAO-B inhibitory activity itself is pharmacologically relevant — at systemic concentrations achievable via non-oral routes, 2C-H could elevate dopamine and phenethylamine levels through MAO-B inhibition.supported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. MAO inhibition may contribute pharmacologically. dta.2494

  • Flanagan et al. (2021) investigated 21 5-HT₂A receptor agonists — spanning phenylalkylamine, ergoline, and tryptamine chemotypes — using a rat-based allergic asthma screening platform and identified 2C-H (2,5-dimethoxyphenethylamine) as the minimal structural unit necessary for anti-inflammatory activity in the 5-HT₂A agonist classsupported

    Investigated 21 agonists at 5-HT2A from three chemotypes (phenylalkylamine, ergoline, tryptamine)... 2C-H identified as the minimal structural unit required for anti-inflammatory effects. acsptsci.0c00063

  • Anti-inflammatory effects showed no correlation with intracellular calcium mobilization (the canonical 5-HT₂A signaling pathway) or with behavioral psychedelic potency, demonstrating that the anti-inflammatory and psychoactive effects of 5-HT₂A agonists are mediated by dissociable signaling pathways.supported

    Anti-inflammatory effects do not correlate with behavioral activity or calcium mobilization via 5-HT2A, suggesting functional selectivity. acsptsci.0c00063

  • This finding was extended by Flanagan et al. (2024), who showed that (R)-DOI and (R)-DOTFM produce comparable in vitro 5-HT₂A activity but divergent anti-inflammatory outcomes in a murine ovalbumin asthma model, confirming functionally selective receptor signaling underlying the anti-inflammatory versus psychedelic effects.supported

    (R)-DOTFM lacks anti-inflammatory activity despite comparable in vitro 5-HT2A binding. Functionally selective anti-inflammatory mechanisms in peripheral tissues. acsptsci.3c00297

  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • Claim in pharmacology — inconclusiveinconclusiveworking →

  • Claim in pharmacology — inconclusiveinconclusiveworking →

safety13 · 11 ok
  • Claim in safety — inconclusiveinconclusiveworking →

  • For the 2C series as a class, reported toxic effects include hallucinations, agitation, aggression, dysphoria, hypertension, tachycardia, seizures, hyperthermia, serotonin toxicity, and sympathomimetic toxidromesupported

    Hallucinations, agitation, aggression, hypertension, tachycardia, seizures, hyperthermia common... Both serotonin toxicity and sympathomimetic presentations seen. s13181-013-0295-x

  • At least five deaths have been attributed to 2C-series compounds in the published literature, all involving pharmacologically active members (2c-e, 2c-i, 2c-b) — none involving 2C-H specifically.partially supported

    At least 5 deaths reported; excited delirium consistent among fatalities. s13181-013-0295-x

  • The potent MAO-B inhibition of 2C-H (IC₅₀ = 1.7 µM) introduces a distinct toxicological consideration independent of serotonergic activitysupported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. MAO inhibition may contribute pharmacologically. dta.2494

  • Gil-Martins et al. (2024) observed mitochondrial dysfunction and oxidative stress in vitro for 2C-T subclass compounds within the broader 2,5-dimethoxyphenethylamine familysupported

    In vitro neurotoxicity of 2C-T-2, 2C-T-4, 2C-T-7... mitochondrial dysfunction, ATP depletion, GSH reduction observed. jox14020044

  • De la Fuente Revenga et al. (2022) demonstrated that repeated 5-HT₂A agonist administration causes receptor downregulation in the frontal cortex, with tolerance observable within 24 hours of a single dosepartially supported

    Repeated DOI induces progressive decrease in head-twitch response (HTR)... 5-HT2AR downregulation in frontal cortex. acschemneuro.2c00170

  • The tolerance mechanism is independent of β-arrestin-2.supported

    Tolerance independent of beta-arrestin-2. acschemneuro.2c00170

  • Claim in safety — inconclusiveinconclusiveworking →

  • Tramadol exerts serotonergic effects through serotonin reuptake inhibition and stimulation of serotonin release. 2C-H compounds this risk through dual mechanisms: weak 5-HT₂A partial agonism and potent MAO-B inhibition (IC₅₀ = 1.7 µM)supported

    Tramadol has serotonergic effects. Higher risk combinations (MAOI + tramadol) must be avoided. s00482-015-1512-0

  • Tramadol exerts serotonergic effects through serotonin reuptake inhibition and stimulation of serotonin release. 2C-H compounds this risk through dual mechanisms: weak 5-HT₂A partial agonism and potent MAO-B inhibition (IC₅₀ = 1.7 µM)supported

    Warning associated with all serotonergic antidepressants combined with tramadol due to serotonin syndrome risk. 0897190013504957

  • Tramadol exerts serotonergic effects through serotonin reuptake inhibition and stimulation of serotonin release. 2C-H compounds this risk through dual mechanisms: weak 5-HT₂A partial agonism and potent MAO-B inhibition (IC₅₀ = 1.7 µM)supported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. dta.2494

  • The MAOI-tramadol combination is specifically identified as a contraindicated pairing in the pain management literature due to serotonin syndrome risk.supported

    Tramadol has serotonergic effects. Higher risk combinations (MAOI + tramadol) must be avoided. s00482-015-1512-0

  • 2C-H's own MAO-B inhibitory activity (IC₅₀ = 1.7 µM) creates a pharmacologically significant interaction with exogenous MAOIssupported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. MAO inhibition may contribute pharmacologically. dta.2494

neuroscience7 · 4 ok
  • Claim in neuroscience — inconclusiveinconclusiveworking →

  • Claim in neuroscience — inconclusiveinconclusiveworking →

  • The identification of 2C-H as an anti-inflammatory pharmacophore implicates a distinct 5-HT₂A signaling pathway dissociated from both calcium mobilization and psychedelic behavioral responsessupported

    Anti-inflammatory effects do not correlate with behavioral activity or calcium mobilization via 5-HT2A, suggesting functional selectivity. acsptsci.0c00063

  • Claim in neuroscience — inconclusiveinconclusiveworking →

  • The anti-inflammatory activity of the 2C-H scaffold may represent a third functionally selective pathway, potentially involving suppression of disease-induced arginase 1 expression as described by Flanagan et al. (2024).supported

    Anti-inflammatory effects of certain psychedelics mediated by suppression of arginase 1 expression... Functionally selective anti-inflammatory mechanisms in peripheral tissues. acsptsci.3c00297

  • Different agonists stabilize distinct receptor conformations that preferentially activate different downstream signaling cascades. 2C-H may preferentially engage the anti-inflammatory signaling conformation while inadequately stabilizing the conformation associated with Gq-mediated calcium mobilization and psychedelic behavioral outputsupported

    Anti-inflammatory effects do not correlate with behavioral activity or calcium mobilization via 5-HT2A, suggesting functional selectivity. acsptsci.0c00063

  • Different agonists stabilize distinct receptor conformations that preferentially activate different downstream signaling cascades. 2C-H may preferentially engage the anti-inflammatory signaling conformation while inadequately stabilizing the conformation associated with Gq-mediated calcium mobilization and psychedelic behavioral outputsupported

    5-HT2A receptor Gq-signaling can be fine-tuned to generate ligands distinct from classical psychedelics. s41467-023-44016-1

receptor-pharmacology6 · 4 ok
  • Receptor binding data for 2C-H derive from NIMH Psychoactive Drug Screening Program (PDSP) profiling, as reported by Psychedelic Science Review and consistent with the receptor profiling methodology described by Ray (2010).supported

    Receptor affinity pharmacology of 25 psychedelic drugs at 51 receptors, transporters, and ion channels (NIMH-PDSP). journal.pone.0009019

  • Data from Wagmann et al. (2019), who tested all compounds using human heterologously expressed MAO-A and MAO-B enzymes with HILIC-HR-MS/MS analysissupported

    17 drugs tested: 12 2Cs... and five FLY analogs. 13 showed MAO-A inhibition, 11 showed MAO-B inhibition. dta.2494

  • Claim in receptor-pharmacology — inconclusiveinconclusiveworking →

  • The anti-inflammatory pharmacophore identification by Flanagan et al. (2021) implies that 2C-H engages a functionally selective signaling pathway at the 5-HT₂A receptor — one that produces anti-inflammatory effects without activating the calcium mobilization cascade associated with psychedelic behavioral outputsupported

    Anti-inflammatory effects do not correlate with behavioral activity or calcium mobilization via 5-HT2A, suggesting functional selectivity. acsptsci.0c00063

  • Claim in receptor-pharmacology — inconclusiveinconclusiveworking →

  • The anti-inflammatory pathway engaged by the 2C-H scaffold may represent a third functionally selective mode, potentially involving suppression of disease-induced arginase 1 expression.supported

    Anti-inflammatory effects of certain psychedelics mediated by suppression of arginase 1 expression... Functionally selective anti-inflammatory mechanisms in peripheral tissues. acsptsci.3c00297

clinical-evidence4 · 4 ok
  • Nau et al. (2015) demonstrated that 5-HT₂A receptor activation prevents allergic asthma in a mouse model, establishing the receptor target as a therapeutic pathway for inflammatory airway disease.supported

    5-HT2A receptor agonist (R)-DOI prevents allergic asthma in ovalbumin mouse model... Suggests 5-HT2 receptor agonists as novel asthma therapy. pmid:25416380

  • Flanagan et al. (2019) showed that 5-HT₂A agonism alleviates airway inflammation and structural remodeling in a chronic mouse asthma model.supported

    (R)-DOI reverses inflammation and symptoms in chronic asthma mouse model via 5-HT2A receptor activation. j.lfs.2019.116790

  • Flanagan et al. (2021) identified 2C-H as the anti-inflammatory pharmacophore for the 5-HT₂A agonist class using a rat-based allergic asthma screening platform — the first study to establish a specific pharmacological significance for 2C-H itself.supported

    2,5-dimethoxyphenethylamine (2C-H) represents the pharmacophore for anti-inflammatory activity... 2C-H identified as the minimal structural unit required for anti-inflammatory effects. acsptsci.0c00063

  • Flanagan et al. (2024) further demonstrated functionally selective anti-inflammatory signaling at 5-HT₂A, with dissociation from psychedelic behavioral output, using (R)-DOI and (R)-DOTFM as comparator compounds in a murine ovalbumin asthma model.supported

    (R)-DOTFM lacks anti-inflammatory activity despite comparable in vitro 5-HT2A binding. Functionally selective anti-inflammatory mechanisms in peripheral tissues. acsptsci.3c00297

comparative-pharmacology4 · 3 ok
  • Claim in comparative-pharmacology — not_supportednot supportedworking →

  • Flanagan et al. (2021) screened 21 5-HT₂A agonists spanning three chemotypes and identified that anti-inflammatory activity tracks with the 2,5-dimethoxyphenethylamine scaffold (2C-H) rather than with psychedelic potencysupported

    Anti-inflammatory effects do not correlate with behavioral activity or calcium mobilization via 5-HT2A... 2C-H identified as the minimal structural unit required for anti-inflammatory effects. acsptsci.0c00063

  • Among 12 2C-series compounds tested by Wagmann et al. (2019), 2C-H showed the lowest IC₅₀ for MAO-B inhibition (1.7 µM), meaning it is both the most susceptible to MAO-B degradation as a substrate and the most potent MAO-B inhibitorsupported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. dta.2494

  • Gil-Martins et al. (2024) characterized neurotoxicity mechanisms for the 2C-T subclass of 2,5-dimethoxyphenethylamines, observing mitochondrial dysfunction and oxidative stress in vitrosupported

    In vitro neurotoxicity of 2C-T-2, 2C-T-4, 2C-T-7... mitochondrial dysfunction, ATP depletion, GSH reduction observed. jox14020044

history3 · 2 ok
  • Claim in history — inconclusiveinconclusiveworking →

  • In 2015, Chapman and Avanes published NMR spectral data confirming the chemical identity of 2C-series grey-market samples, contributing analytical reference standards for forensic identification.supported

    1H NMR spectra of 28 alleged psychedelic phenylethanamines from 15 grey-market internet vendors. Members from each principal phenylethanamine family analyzed: eleven para-substituted 2,5-dimethoxyphenylethanamines (2C and 2C-T series). isomerdesign-1

  • The compound's pharmacological significance gained independent recognition in 2021, when Flanagan et al. identified 2C-H as the anti-inflammatory pharmacophore for 5-HT₂A receptor agonists in a rat model of allergic asthmasupported

    2,5-dimethoxyphenethylamine (2C-H) represents the pharmacophore for anti-inflammatory activity... 2C-H identified as the minimal structural unit required for anti-inflammatory effects. acsptsci.0c00063

pharmacokinetic-detail3 · 0 ok
  • Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →

  • Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →

  • Claim in pharmacokinetic-detail — inconclusiveinconclusiveworking →

summary3 · 2 ok
  • Its primary research significance emerged in 2021, when Flanagan et al. identified the 2,5-dimethoxyphenethylamine scaffold as the anti-inflammatory pharmacophore for 5-HT₂A receptor agonists, establishing a pharmacological role for 2C-H independent of psychoactivity.supported

    2,5-dimethoxyphenethylamine (2C-H) represents the pharmacophore for anti-inflammatory activity... 2C-H identified as the minimal structural unit required for anti-inflammatory effects. acsptsci.0c00063

  • It is the most potent MAO-B inhibitor among tested 2C compounds (IC₅₀ = 1.7 µM), a property that both explains its oral inactivity through rapid first-pass deamination and introduces pharmacologically relevant monoamine oxidase interactionssupported

    2C-H had the lowest MAO-B IC50 (most potent MAO-B inhibitor in the series) at 1.7 µM. MAO inhibition may contribute pharmacologically. dta.2494

  • Claim in summary — inconclusiveinconclusiveworking →

chemistry1 · 1 ok
  • Marcher-Rørsted et al. (2020) demonstrated that removal of either methoxy group produces modest reductions in in vitro receptor affinity but significant loss of in vivo psychedelic activity (measured by head-twitch response in mice), confirming that both methoxy groups contribute to the compound's receptor engagement geometrysupported

    Elimination of either the 2- or 5-methoxy group leads to modest drop in binding affinity... Trend not mirrored in vivo — removal of either methoxy group resulted in significant reduction in head-twitch response in mice. acschemneuro.0c00129

3Sources

22 consumed · sorted by year · feeds = sections resting on it

Sources
yearsourcetierstatusfeeds
20242C-H — Psychedelic Science Reviewurl:e8329dd4b64e4d05weakconsumedcited only
20242C-H — Wikipediaurl:1adf76812e485a96weakconsumedcited only
2024Mechanistic Insights into the Neurotoxicity of 2,5-Dimethoxyphenethylamines (2C) and Corresponding N-(2-methoxybenzyl)phenethylamine (NBOMe) DrugsGil-Martins E, Cagide-Fagin F, Martins D, Borer A, Barbosa DJ, Fernandes C, Chavarria D, Remiao F, Borges F, Silva R · Journal of Xenobioticsdoi:10.3390/jox14020044moderateconsumed2 sections
2024NIST WebBook — 2,5-Dimethoxyphenethylamine (CAS 3600-86-0)url:470e25442add4d1bweakconsumedcited only
2024Serotonin-2 Receptor Agonists Produce Anti-inflammatory Effects through Functionally Selective Mechanisms That Involve the Suppression of Disease-Induced Arginase 1 ExpressionFlanagan TW, Foster TP, Galbato TE, Lum PY, Louie B, Song G, Halberstadt AL, Billac GB, Nichols CD · ACS Pharmacology & Translational Sciencedoi:10.1021/acsptsci.3c00297moderateconsumed4 sections
2023Identification of 5-HT2A receptor signaling pathways associated with psychedelic potentialWallach J, Cao AB, Calkins MM, Heim AJ, Lanham JK, et al. · Nature Communicationsdoi:10.1038/s41467-023-44016-1moderateconsumed2 sections
2022Tolerance and Cross-Tolerance among Psychedelic and Nonpsychedelic 5-HT2A Receptor Agonists in Micede la Fuente Revenga M, Jaster AM, McGinn J, Silva G, Saha S, Gonzalez-Maeso J · ACS Chemical Neurosciencedoi:10.1021/acschemneuro.2c00170moderateconsumed1 section
2021Structure-Activity Relationship Analysis of Psychedelics in a Rat Model of Asthma Reveals the Anti-Inflammatory PharmacophoreFlanagan TW, Billac GB, Landry AN, Sebastian MN, Cormier SA, Nichols CD · ACS Pharmacology & Translational Sciencedoi:10.1021/acsptsci.0c00063moderateconsumed7 sections
2020Designer drugs: mechanism of action and adverse effectsLuethi D, Liechti ME · Archives of Toxicologydoi:10.1007/s00204-020-02693-7strongconsumed2 sections
2020Investigation of the 2,5-Dimethoxy Motif in Phenethylamine Serotonin 2A Receptor AgonistsMarcher-Rørsted E, Halberstadt AL, Klein AK, Chatha M, Jademyr S, Jensen AA, Kristensen JL · ACS Chemical Neurosciencedoi:10.1021/acschemneuro.0c00129moderateconsumed3 sections
20195-HT2 receptor activation alleviates airway inflammation and structural remodeling in a chronic mouse asthma modelFlanagan TW, Sebastian MN, Battaglia DM, Foster TP, Cormier SA, Nichols CD · Life Sciencesdoi:10.1016/j.lfs.2019.116790moderateconsumed1 section
2019Interactions of phenethylamine-derived psychoactive substances of the 2C-series with human monoamine oxidasesWagmann L, Brandt SD, Stratford A, Maurer HH, Meyer MR · Drug Testing and Analysisdoi:10.1002/dta.2494moderateconsumed6 sections
2018Comparative neuropharmacology of N-(2-methoxybenzyl)-2,5-dimethoxyphenethylamine (NBOMe) hallucinogens and their 2C counterparts in male ratsElmore JS, Decker AM, Sulima A, Rice KC, Partilla JS, Blough BE, Baumann MH · Neuropharmacologydoi:10.1016/j.neuropharm.2018.02.033moderateconsumed1 section
2015PeakAL: Protons I Have Known and Loved — NMR spectra of psychedelic phenylethanamines including TMA-2Chapman SJ, Avanes AAdoi:10.16889/isomerdesign-1weakconsumed1 section
2015Serotonin 5-HT2 receptor activation prevents allergic asthma in a mouse modelNau F, Miller J, Saravia J, Ahlert T, Yu B, Happel KI, Cormier SA, Nichols CD · American Journal of Physiology - Lung Cellular and Molecular Physiologypmid:25416380moderateconsumed1 section
2015Serotonin syndrome and pain medication: What is relevant for practice?Schenk M, Wirz S · Schmerzdoi:10.1007/s00482-015-1512-0moderateconsumed1 section
2014Serotonin syndrome: is it a reason to avoid the use of tramadol with antidepressants?Park SH, Wackernah RC, Stimmel GL · Journal of Pharmacy Practicedoi:10.1177/0897190013504957weakconsumed1 section
20132C or Not 2C: Phenethylamine Designer Drug ReviewDean BV, Stellpflug SJ, Burnett A, Engebretsen KM · Journal of Medical Toxicologydoi:10.1007/s13181-013-0295-xstrongconsumed4 sections
2010Metabolism of designer drugs of abuse: an updated reviewMeyer MR, Maurer HH · Current Drug Metabolismpmid:20540700moderateconsumed2 sections
2010Psychedelics and the human receptoromeRay TS · PLoS ONEdoi:10.1371/journal.pone.0009019moderateconsumed1 section
1991PiHKAL: Phenethylamines I Have Known and LovedShulgin AT, Shulgin Aurl:69f8f06ae20edef6weakconsumedcited only
1966Role of 3,4-dimethoxyphenethylamine in schizophreniaShulgin AT, Sargent T, Naranjo C · Naturepmid:21105535moderateconsumed1 section
—Searched PubMed for "2C-H 2,5-dimethoxyphenethylamine pharmacology" — no resultsabsenceno results—
—Searched PubMed for "DMPEA dimethoxyphenethylamine psychedelic schizophrenia" — no resultsabsenceno results—

4Docket

one filing per activity — decisions, correspondence, reports

  1. 0012026-05-11revisionRevision 1

    Initial LLM generation (v5 pipeline, wiki, prose phase)

    psx:substance/2c-h/version/1
  2. 0022026-05-11proposalduration · oral · totalrejectedworking →
  3. 0032026-06-04proposal19 value proposals approved together

    one review action inferred from a shared reviewer and instant — the graph records one activity per proposal

    19 items in this filing

    • contraindication · other
    • contraindication · other
    • contraindication · cardiovascular
    • contraindication · neurological
    • contraindication · psychiatric
    • toxicity
    • dependence · full
    • withdrawal
    • tolerance
    • dosage · oral
    • dose_tier · threshold
    • dose_tier · light
    • dose_tier · common
    • dose_tier · strong
    • dose_tier · heavy
    • timeline · oral · onset
    • timeline · oral · peak
    • timeline · oral · afterglow
    psx:substance/2c-h/proposal/contraindication/034ae47d-636b-46ca-9b2a-6d44ab03ec3f
  4. 0042026-06-04publicationPublication — backfill

5Issued documents

what the notice, info card and emergency page said, by hash

Issued documents
documentcontent hashissuedfrom versionsuperseded
emergencyc15c760aabf6f0fcf5b6fc6b…2026-10-19 20:29Revision 1current
info_cardf8f8bf78a7804b98fa151e95…2026-10-19 20:29Revision 1current
notice53ffc98bc5c175e403d133df…2026-10-19 20:29Revision 1current
emergency3f0909c25c714d225b4bb3e3…2026-09-04 04:27Revision 1superseded2026-10-19
info_cardc977c8678c50584a7e1fc140…2026-09-04 04:27Revision 1superseded2026-10-19
notice64878b43a1d2932a5305f55b…2026-09-04 04:27Revision 1superseded2026-10-19