4F-4-MAR
Limited data
Limited data
Sparse data. Doses and effects may be unreliable or untested.
- 1 source
- duration data present
- 18 combo interactions documented
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
- 1 source
- duration data present
- 18 combo interactions documented
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
Aliases: 4-fpo, 4f-mar, Pf-4-mar
Summary
4F-4-MAR first appeared in Slovenia (2018) and was forensically confirmed via HR-MS and NMR. The para-fluoro substitution raises lipophilicity and slows oxidative metabolism, explaining >16 hour subjective duration. User reports highlight pronounced anorexia, clean but long-lasting stimulation and muted euphoria compared to classic 4-MAR.
Dose Information
| ROA | Threshold |
|---|---|
| Oral | 5mg |
| Insufflated | 15mg |
Only a threshold dose is documented for this substance — the smallest amount with a noticeable effect. There is no published light/common/strong ladder to show above it.
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 15-45 min | 30-90 min | 2-6 hrs | 6-10 hrs | 8.75-18.25 hrs |
| Insufflated | 5-15 min | 15-45 min | 2-6 hrs | 6-10 hrs | 8.33-17 hrs |
Effect Profile
Scores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Weighted by importance: core (×3), major (×2), minor (×1)
Strong anxiety/jitters and stimulation with moderate focus, mild euphoria
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track 4F-4-MAR there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
4F-4-MAR Source: SubstanceSearch (substancesearch.com) Oral dose (mg): threshold 5 Insufflated dose (mg): threshold 15 Oral duration: onset 15-45m · come-up 0.5-1.5h · peak 2-6h · offset 6-10h · total 8.75-18.25h · after-effects 6-24h Insufflated duration: onset 5-15m · come-up 15-45m · peak 2-6h · offset 6-10h · total 8.33-17h · after-effects 6-24h Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
The app keeps custom substances simple, so the full dose ranges live in the description text above. Ranges are harm-reduction guidance, not a prescription.
Tolerance
Tolerance Decay
Acute tolerance: develops within a single session — the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Effects
- Stimulation
- Increased energy
- Increased heart rate
- Vasoconstriction
- Bruxism
- Insomnia
- Teeth grinding
- Increased blood pressure
- Pupil dilation
- Increased perspiration
- Focus enhancement
- Motivation enhancement
- Euphoria
- Alertness enhancement
- Wakefulness
- Increased sociability
- Anxiety
- Compulsive redosing
- Talkativeness
- Thought acceleration
- Increased libido
- Increased music appreciation
- Visual enhancement
- Tactile enhancement
- Appetite suppression
- Light sensitivity
- Dehydration
- Disinhibition
- Double vision
- Dulled perception
Combinations
Cross-Check 4F-4-MAR with another substanceHelpful Links
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