2C-I
2C-I is a synthetic phenethylamine psychedelic and member of the 2C-x family, a group of compounds derived through systematic modifications of mescaline. Alexander Shulgin synthesized it in 1976 and included it in PiHKAL, published in 1991.citation needed Often compared to 2C-B though less widely used, 2C-I gained popularity as a recreational psychedelic in the late 1990s. It is sometimes confused with the more dangerous analog 25I-NBOMe.
Dosage & Duration
Dosage
Doses are population estimates that vary widely between individuals.
Effects respond steeply to small dose changes; a difference of as little as 2 mg can noticeably alter intensity, so gradual titration is advised. Doses above 35 mg can be unpleasantly strong even for experienced users.
Duration
Subjective Effects
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Effects vary widely by individual, dose, and context.
Physical
Cognitive
The head space of 2C-I is described by many as one which is relatively normal in its thought processes even at moderate to high dosages. It is often said to lack insight when compared to that of 2C-E, 2C-B and LSD.
Visual
Distortions
Geometry
The visual geometry of 2C-I can be described as more similar in appearance to that of LSD or 2C-B than that of 2C-E, psilocin, or ayahuasca although it is much more bland and less detailed. They can be comprehensively described as unstructured in their organization, algorithmic in geometric style, intricate in complexity, large in size, fast and smooth in motion, colourful in scheme, glossy in colour, both soft and sharp in their edges as well as equally rounded and angular in their corners. They seem high in algorithmic visuals such as fractals and at higher dosages are significantly more likely to result in states of Level 7A visual geometry over Level 7B.
Hallucinatory States
Like LSD, while 2C-I is capable of producing a full range of low and high level hallucinatory states, this is extremely rare and inconsistent at higher levels but common at lower levels.
Auditory
See also: Psychedelic Intensity Scale, Effects of psychedelics (visual, cognitive, miscellaneous)
Reagent Testing
Expected colorimetric results for common reagent tests. Colors show reaction change over 1–2 minutes.
Pharmacology
Pharmacodynamics
2C-I has assay-dependent signaling at human serotonin receptors. In recombinant-cell assays it was a full agonist at 5-HT2A and 5-HT2C receptors in the inositol-phosphate pathway, but an antagonist at 5-HT2A in an arachidonic-acid-release assay. It also had moderate affinity but very low functional potency at the serotonin transporter. These results support a serotonergic mechanism while cautioning against describing 2C-I with one unqualified efficacy label. [S1]
Pharmacokinetics
Experiments with recombinant human enzymes identified MAO-A and MAO-B as the major enzymes catalyzing 2C-I deamination to its corresponding aldehyde. [S2] In rats, 2C-I also underwent O-demethylation at both methoxy positions, N-acetylation, and deamination followed by oxidation or reduction; the parent compound and many metabolites were partly excreted as conjugates. [S3] The rat study did not have authentic human urine, so this metabolite pattern must not be presented as a confirmed human profile. [S3]
Dangerous
Highest riskThese combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.
Unsafe
AvoidThere is considerable risk of physical harm when taking these combinations, they should be avoided where possible.
Caution
Use cautionThese combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.
Tolerance
Tolerance timelines are rules of thumb, not exact schedules, and vary widely between individuals and use patterns.
Serotonergic psychedelicscitation needed
Harm Potential
Addiction & Dependence
Psychological
Extremely Low2C-I is not considered habit-forming and the desire to use it may actually decrease with repeated use, consistent with classical psychedelics. Some individuals may use it more frequently than intended, but psychological dependence is unlikely.
Physical
Extremely Low2C-I is not physically addicting and withdrawal effects following discontinuation have not been reported.
Psychosis Risk
As with psychedelics generally, 2C-I may trigger latent psychological and mental problems in susceptible individuals. Those with a family history of schizophrenia or early onset mental illness should exercise extreme caution. Acute psychological effects such as disorientation, confusion, anxiety, and fear of death may occur during intoxication.
History & Culture
Discovery and Synthesis
2C-I was first synthesized and investigated for human activity by Alexander Shulgin in the mid-to-late 1970s. The compound was initially described in scientific literature in 1977citation needed, with its properties and effects in humans documented the following year. Shulgin later provided a…
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Legality
International
1961 Single Convention: 2C-I is not individually scheduled.
1971 Convention on Psychotropic Substances: Schedule I.
1988 Convention: 2C-I is not listed in precursor Tables I or II.
By Country
References
Source Pages
Citations
- Alexander Shulgin, & Ann Shulgin. (1991). PiHKAL: A Chemical Love Story. Transform Press. https://erowid.org/library/books_online/pihkal/pihkal033.shtml1
- Therapeutic Goods (Poisons Standard—June 2026) Instrument 2026. legislation.gov.au (n.d.). https://www.legislation.gov.au/F2026L00633/asmade/2026-05-28/text/original/epub/OEBPS/document_1/document_1.html1
- Suchtgiftverordnung (SV), current RIS consolidated text. ris.bka.gv.at (n.d.). https://www.ris.bka.gv.at/GeltendeFassung/Bundesnormen/10011053/Suchtgiftverordnung%2c%20Fassung%20vom%2027.08.2026.pdf1
- Suchtmittelgesetz (SMG), current RIS consolidated text. ris.bka.gv.at (n.d.). https://www.ris.bka.gv.at/GeltendeFassung/Bundesnormen/10011040/SMG%2c%20Fassung%20vom%2027.08.2026.pdf1
- Suchtgift-Grenzmengenverordnung (SGV), current RIS consolidated text. ris.bka.gv.at (n.d.). https://www.ris.bka.gv.at/GeltendeFassung/Bundesnormen/10011056/Suchtgift-Grenzmengenverordnung%2c%20Fassung%20vom%2027.08.2026.pdf1
- UNODC Global Synthetic Drugs Assessment 2020. unodc.org (n.d.). https://www.unodc.org/documents/scientific/Global_Synthetic_Drugs_Assessment_2020.pdf1
- Neue-Psychoaktive-Substanzen-Gesetz (NPSG), current RIS consolidated text. ris.bka.gv.at (n.d.). https://www.ris.bka.gv.at/GeltendeFassung/Bundesnormen/20007605/NPSG%2c%20Fassung%20vom%2027.08.2026.pdf1
- Arrêté royal du 18 octobre 2004 modifiant l'arrêté royal du 22 janvier 1998 réglementant certaines substances psychotropes. ejustice.just.fgov.be (n.d.). https://www.ejustice.just.fgov.be/eli/arrete/2004/10/18/2004022875/justel1
- Arrêté royal du 6 septembre 2017 réglementant les substances stupéfiantes et psychotropes. ejustice.just.fgov.be (n.d.). https://www.ejustice.just.fgov.be/eli/arrete/2017/09/06/2017031231/justel1
- Annexe IV non-official consolidated version (AFMPS), Annex IVa. afmps.be (n.d.). https://www.afmps.be/sites/default/files/content/INSP/NARC/annex%20IV_non%20official%20consolidated%20version.pdf1
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Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more
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