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    🧪 This is a research chemical with limited data on its long-term health effects, toxicity profile, and safe dosage ranges.

    4-MAR Limited data
    Limited data
    Sparse data. Doses and effects may be unreliable or untested.
    • 4 corroborating sources
    • 4 ROAs with full dose ladders
    • duration data present
    • 29 combo interactions documented
    • classified Tentative
    • classified Research-chemical
    • dose data not in PW/TripSit (unverifiable)
    • dose ladder unverifiable and undisclosed — capped

    Aliases: Ice, U4ea, U4euh, 4-max, Euphoria

    Stimulant Research-chemical

    Summary dose.wiki Erowid TripSit

    4-MAR exists as cis- and trans-stereoisomers; recreational preparations typically contain racemic cis-4-MAR. Users report clear empathic stimulation with minimal peripheral side effects at moderate doses (10-20 mg), but pronounced vasoconstriction and compulsive redosing at higher doses. Vaporization produces intense rapid onset despite maintaining 6-8 hour duration.

    Dose Information source varies by band

    ROA Light Common Strong Heavy
    Oral 1-5mg 5-10mg 10-15mg 15-20mg+
    Insufflated 5-10mg 10-30mg 30-50mg 50mg+
    Smoked / Vaporized 5-10mg 10-20mg 30-60mg 60mg+
    Intravenous 5-10mg 10-20mg 20-40mg 40mg+
    Light Common Strong Heavy
    Sources· 4 of 4 ladders not fully identified

    Oral

    Dose ladder — Light–Strong: DrugsPRO · Heavy: not identified

    Insufflated

    Dose ladder — source not identified

    Smoked / Vaporized

    Dose ladder — source not identified

    Intravenous

    Dose ladder — source not identified

    Onset, Duration & After-effects dose.wiki TripSit

    ROA Onset Comeup Peak Offset After Effects Total
    Oral 0.75-2 hrs 1-2 hrs 2-4 hrs 4-10 hrs 48 hrs 7.75-18 hrs
    Insufflated 20-40 min 30-60 min 1-3 hrs 3-6 hrs 48 hrs 4.83-10.67 hrs
    Smoked / Vaporized 0-1 min 5-15 min 1-3 hrs 4-8 hrs 48 hrs 5.08-11.27 hrs

    Effect Profile

    Scores (0–10) curated from multiple sources:

    • Effect keyword matching from PsychonautWiki catalog
    • Weighted by importance: core (×3), major (×2), minor (×1)

    Full methodology

    Stimulant 5.6
    Strong 6/10

    Moderate stimulation and euphoria with strong anxiety/jitters, mild focus

    Stimulation / Energy ×3
    7
    stimulation increased energy wakefulness
    Euphoria / Mood Lift ×2
    7
    euphoria cognitive euphoria motivation enhancement
    Focus / Productivity ×2
    5
    focus enhancement motivation enhancement
    ⚠ Anxiety / Jitters ×1
    10
    anxiety teeth grinding increased heart rate bruxism vasoconstriction
    View methodology →

    Tolerance

    Build-up develops over days to weeks of regular use
    Reset 3–7 days for acute; 1–3 weeks for full reset

    Tolerance Decay

    Full tolerance 1d Half tolerance 12d Baseline ~21d

    Effects dose.wiki

    Positive
    Negative
    Positive
    Negative
    Neutral
    Positive
    Negative
    Neutral

    Combinations TripSit

    Cross-Check 4-MAR with another substance

    Community 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.

    Bluelight 3 threads 2 positive 1 neutral visit
    4 Mar First Time Euphoria positive

    4-methylaminorex - First Time - EUPHORIA!!!! I had heard about Ice (4-methylaminorex) and it caught my attention. It seemed almost too good to be true,and also extremely rare. I had also been interested in methamphetamine so when I found an 'Ice' connection I naturally jumped at the chance.

    4 Mar Ice 1st Time Amped Still Awaiting Comedown neutral

    Ice (4-MAR) - 1st time - Amped & Still Awaiting Comedown 1am - at friend's house. was actually planning on chilling sober and kickin' it. i watch the others go at the crystals. i get ancy and decided ive changed my mind. 115am - paul van dyk on the CD player. place roughly 10mg of 4-MAR on a square of foil.

    10 mg mentioned in the thread; auto-extracted, unverified
    4 Mar First Time One Gram Ten Electric Days positive

    Some background: It was 2010. I was 21 at the time. I wasn't really into stimulants. I'd had coke a few times, usually in combination with other things. Methamphetamine made me feel jumpy. My skin would tingle and I'd feel as if I was breaking out in cold sweats. Not my thing.

    4-MAR's nerd page Pharmacology, chemical data, effect profiles, and more
    →

    Helpful Links

    📖 dose.wiki 📖 TripSit
    Import into PsychonautWiki Journal

    The PsychonautWiki Journal app includes 4-MAR, but its built-in data can be thinner than ours. Importing this file adds a separate "4-MAR (Substance Search)" custom substance with our dose ranges, durations and tolerance, so you can log against whichever you prefer.

    ⬇ Download import file Import this file as custom substances and you get "4-MAR (Substance Search)" with every route's full dose ladder and timeline, no typing. Works on iOS and Android (v15+); the format is confirmed by the app's developer.

    Ranges are harm-reduction guidance, not a prescription.