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. Historical case reports link chronic use to pulmonary hypertension. Harm reduction includes maintaining cool ambient temperature, frequent hydration, and magnesium supplementation to reduce bruxism.
Also known as: Ice, U4ea, U4euh, 4-max, Euphoria, McN-822, 4-Methylaminorex
Classification
Chemical: Aminorex
Psychoactive: Stimulant
Tag: Anorectic
Tag: Habit-Forming
Tag: Research-Chemical
Tag: Tentative
Effects
Stimulation
Teeth Grinding
Vasoconstriction
Increased Heart Rate
Insomnia
Loss Of Appetite
Euphoria
Cognitive Euphoria
Motivation Enhancement
Focus Enhancement
Increased Sociability
Empathy Enhancement
Appetite Suppression
Increased Libido
Light Sensitivity
Dehydration
Bodily Control Enhancement
Increased Music Appreciation
Routes of Administration
Oral
Dosage
Threshold: 2-5 mg
Light: 5-10 mg
Common: 10-25 mg
Strong: 25-40 mg
Heavy: 40+ mg
Dangerous: 40 mg
Duration
Onset: 0.75-2 h
Comeup: 1-2 h
Peak: 2-4 h
Offset: 4-10 h
After Effects: 10-48 h
Total Duration: 8-16 h
Insufflated
Dosage
Threshold: 2-5 mg
Light: 5-10 mg
Common: 10-20 mg
Strong: 20-35 mg
Heavy: 35+ mg
Duration
Onset: 0.33-0.67 h
Comeup: 0.5-1 h
Peak: 1-3 h
Offset: 4-10 h
After Effects: 10-36 h
Total Duration: 5-12 h
Vaporized / Smoked
Dosage
Threshold: 1-3 mg
Light: 3-7 mg
Common: 7-15 mg
Strong: 15-25 mg
Heavy: 25 mg
Duration
Onset: 0-0.02 h
Comeup: 0.08-0.25 h
Peak: 1-3 h
Offset: 4-8 h
After Effects: 48 h
Smoked
Dosage
Heavy: 25+ mg
Light: 5-10 mg
Common: 10-20 mg
Strong: 20-25 mg
Threshold: 5 mg
Duration
Onset: 0.02-0.05 h
Peak: 0.5-1 h
Offset: 4-10 h
After Effects: 8-36 h
Total Duration: 6-12 h
Harm Reduction
Check interactions before mixing substances, pay attention to dose spacing and hydration, and treat all dosage guidance as approximate rather than guaranteed safe.
Sources
Substance data is aggregated from the following public harm-reduction and reference sources.
This static page is intended as a readable non-JS and prerender-friendly library export.
Get the full DrugsPRO experience
Open the interactive DrugsPRO app for search, saved items, interactions, and deeper harm reduction tools.
Get the PRO test kit. The simple, quick and reliable drug checking test kit. Visit https://protestkit.eu
4-MAR - DrugsPRO substancijos vadovas
4-MAR: 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. Vapo
