On one of the last days of this past spring semester, as a celebration of the onset of summer vacation, my friends and I decided it would be fun to trip on acid. However, our acid contact had gone out of town for the day, so I went to find some mushrooms instead.
2C-I
Well-documented
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 5 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 28 combo interactions documented
- toxicity data (PsychonautWiki)
- classified Research-chemical
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 5 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 28 combo interactions documented
- toxicity data (PsychonautWiki)
- classified Research-chemical
Aliases: 2ci
Summary
2,5-Dimethoxy-4-iodophenethylamine (also known as 2C-I and "Smiles") is a psychedelic substance of the phenethylamine class. It is a member of the 2C-x family of psychedelic phenethylamines, all of which were derived from the systematic modification of the mescaline molecule. 2C-I was first synthesized and investigated for human activity by Alexander Shulgin in 1976 and later described in his 1991 book PiHKAL ("Phenethylamines I Have Known and Loved").
Perspectives
“The 2C family can feel like entirely different drugs depending on how you administer them. The oral ROA is an entirely different experience than insufflated. This is chiefly in the timing- you come up fast and hard, you get faceplanted into the experience from the top of a 12 story building, rather than the slow descent the oral ROA gives you.”
“I was present at a group meeting, but was only an observer. With zero milligrams of 2C-I, I was able to get to a delightful plus 2.5 in about five minutes after I arrived at your place, and absorbed the ambience of the folks who had actually imbibed the material. My level lasted about four hours and came down at about the same time as did the others. There were no after-effects experienced except for a pleasant languor.”
“Overall, on this dose this was a fairly mild and pleasant experience. It didn't have the depth of 2C-E, or a great deal of excitement, but for a gentle afternoon sojourn it was positive and enjoyable.”
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 5-10mg | 10-20mg | 20-30mg | 30mg+ |
Light
Common
Strong
Heavy
Sources
Oral
Dose ladder — PsychonautWikiOnset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 12-48 min | 48-90 min | 3-5 hrs | 2-3 hrs | 5-10 hrs |
Effect Profile
650 reportsScores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Validated against 508 Erowid trip reports
- Weighted by importance: core (×3), major (×2), minor (×1)
Psychedelic
8.8
Intense+
9/10
Strong visuals, headspace, auditory effects, and body load
Visual Intensity
×3
10
external hallucinations
internal hallucinations
autonomous entities
colour enhancement
drifting
synaesthesia
+7 more
Headspace Depth
×3
10
emotion enhancement
perspective alterations
confusion
time distortion
Auditory Effects
×1
10
auditory distortion
auditory enhancement
auditory hallucinations
auditory hallucination
synaesthesia
Body Load / Somatic Effects
×1
10
nausea
temperature regulation suppression
muscle tension
increased heart rate
Tolerance
Build-up
develops rapidly after a single use
Reset
7β14 days for baseline
Tolerance Decay
Half tolerance
5d
Baseline
~10d
Subjective tolerance to classical psychedelics rises acutely and tends to decrease substantially over 3β7 days and return near baseline by 1β2 weeks; crossβtolerance across serotonergic psychedelics is common, though exact ratios are not quantified.
Cross-tolerance
Effects
Aggregated from 508 Erowid and 142 Bluelight experience reports
Each bar shows the share of analyzed reports whose text mentions that effect — a mention is not always a first-hand experience (fear of an effect, something witnessed, or "did not happen" count too). Tap or hover any number for details. The second value is the Bluelight extractor's per-effect confidence; a dash means the row is Erowid-derived, which has no confidence measurement.
Effect glossary — · full glossary
Positive Effects 78
77.5%
79%
53.7%
87%
50.7%
86%
48.0%
86%
45.5%
90%
42.1%
88%
38.0%
84%
36.9%
82%
36.0%
87%
30.5%
85%
28.0%
85%
28.0%
88%
25.8%
82%
24.7%
93%
24.4%
85%
24.0%
84%
22.0%
86%
22.0%
87%
22.0%
87%
20.0%
86%
Adverse Effects 42
42.5%
86%
30.3%
85%
29.7%
85%
22.0%
84%
16.0%
83%
15.2%
81%
12.0%
85%
12.0%
83%
12.0%
75%
11.6%
68%
8.0%
89%
8.0%
81%
6.0%
80%
6.0%
84%
5.9%
–
5.5%
77%
5.2%
84%
4.0%
85%
4.0%
80%
4.0%
82%
Combinations
Cross-Check 2C-I with another substanceCommunity Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, Bluelight, and Dose.wiki. Click a source to expand. Reports are harm-reduction context, not medical guidance. Tags summarise each author's own verdict — how reports are classified.
Erowid 8 reports 2 positive 5 neutral 1 cautionary visit
Recently I've begun a significant life-changing process of self-betterment through a psychedelic regimen, by clearing my head space of negativity and re-opening my imagination, internal imaging capabilities, and routes of self-expression.
New Year's Eve had arrived and I was in the mood for something different. Our destination was a small rave, so I was looking for something that would give me energy and be fun to dance to without leaving me too incoherent.
Prior to this experience there were 3 others, all which had mild similar experience to those of others. But this one went terrible wrong or really good depending upon how you look at it. I took 22mg crystal form.
Method: 3 doses; insufflation [00:00], oral (under tongue[00:30]) + (ingestion[02:00]) Length: 15 hours; 23:30pm? to 15:30pm Recovery: 5 days + (still somewhat recovering) Date: 28th December 2012 This is my first and only hallucinogenic experience to date, bar a terrible bout of misplaced anxiety and disgust on synthe...
I had tried MDMA 2011-2012 but only properly experienced it in April, and since then have had it many times and Mkat/similar. With that, IΒve started using nitrous oxide and weed occasionally too, but really am interested in exploring what drugs have to offer, especially with altered states of consciousness.
It had been a strange few weeks and months, a time of transition, confusion, and angst. Time seemed to be throwing a curveball backward at me from some point, shrouded and viscerally ominous, in the future.
I'm a long-time dabbler in psychedelics, but have never before felt the compulsion to post an experience. I've tried marijuana, salvia, DXM, Woodrose-derived LSA, LSD, shrooms, 2C-E, 2C-I, 4-AcO-DMT, 5-Meo-DMT, 5-Meo-DIPT, ayahuasca and catcus-derived mescaline --- but I've never done a dosage, on anything, that would...
Bluelight 8 threads 1 positive 6 neutral 1 cautionary visit
Friday night at college and my boy got some acid, and I missed the movie I wanted to see. Thank goodness he has some extra 2C-I around. I wasn't sure I really wanted to trip on it again because my first experience was unpleasant until I smoked weed mid-peak.
2C-I β First time, relatively inexperienced, 20mg β Fantastic, BUT β¦ Story Background This is one of a number of stories a friend found hand-written on notepad paper and stuffed inside a chemistry book at the University library.
It was about 9:30 when I decided to introduce someone into the wonderful world of hallucinogens with my own desire to attempt to increase my connectivity and understanding of this man.
Compound 2,5-Dimethoxy-4-iodophenethylamine hydrochloride, 2C-I HCl Dosage 14.2 Β± 0.4 mg (based on rated accuracy of the scale and volumetric solution). Purity m.p. 243 - 245 Β°C with decomposition (PiHKAL: 246 - 247 Β°C).
This report was written by me the day after this trip, about 5 months ago or so. I'd have probably written it differently and explained some things in a different way had I written it now, but I decided not to re-write it because it is no longer fresh in my mind.
2c-i - first time - quite nice --------------- introduction --------------- it's 12:35 am and i have just gotten home from work and ate a sandwhich i picked up from wendy's. i worked from 6pm-midnight. i took the 16mg dose at 10:15 am.
Me: 120mg 2ci, 125lbs Boyfriend: 130mg 2ci, round 30mg 2ce, 160lbs. Empty stomachs Both somewhat experienced trippers, my boyfriend more so than me. So this is a long report; if you don't want to read all of it here are the basics: Planning a light trip, we dose the 2ci wrong by a factor of ten - yes TEN.
This should be a lesson for all of you to NEVER EVER eyeball a dose. If this had been a more dangerous substance, I could have ended up the hospital. After the trip, I took the small plastic baggy that the contents came in and it measured out to 62mg's. So I took around 40mg's+.
Dose.wiki 2 reports 1 positive 1 neutral visit
2C-I has been sold under the line βItβs a lot like acidβ and I can see why. In terms of headspace and physical effects, it is very similar, although it is more stimulating, and although similar the body high leans more towards other 2Cs. The visuals are alsoβ¦
The 2C family can feel like entirely different drugs depending on how you administer them. The oral ROA is an entirely different experience than insufflated. This is chiefly in the timing- you come up fast and hard, you get faceplanted into the experienceβ¦
Bluelight Reference Guide
Phenethylamines The Big & Dandy 2C-I Thread - Take Two
Welcome to the Big & Dandy 2C-I Thread 2C-I = 2,5-dimethoxy-4-iodophenethylamine ; structural formula on the left ; 2C-I powder on the right (photo courtesy of the ruling Erowid.org) External Information Links: Erowid 2C-I Vault (experience reports) PIHKAL Entry for 2C-I Wikipedia entry Previous Big & Dandy Thread: Fir...
Read full thread on Bluelight βPiHKAL / TiHKAL
PiHKAL #33: 2C-I
“I was present at a group meeting, but was only an observer. With zero milligrams of 2C-I, I was able to get to a delightful plus 2.5 in about five minutes after I arrived at your place, and absorbed the ambience of the folks who had actually imbibed the material. My level lasted about four hours and came down at about the same time as did the others. There were no after-effects experienced except for a pleasant languor.”
2C-I's nerd page
Pharmacology, chemical data, effect profiles, and more
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Helpful Links
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