Trip report for 4-Fluoroethylphenidate Source, no details, QA only: Highly reliable Canadian vendor, Subject: 140lbs, 6', 45yo males with wide experience in RC's, though not focused on stimulants Appearance: White, fluffy powder Notes: Don't try to vape this, it's caustic and doesn't seem to work.
4F-EPH
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 4 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- toxicity data (PsychonautWiki)
- classified Tentative
- classified Research-chemical
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 4 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- toxicity data (PsychonautWiki)
- classified Tentative
- classified Research-chemical
Aliases: 4f-tep, 4-fluoroethylphenidate, 4-feph
Summary
4F-EPH is a novel research chemical with minimal human use history and unknown long-term toxicity. First reported death occurred in 2016 involving polydrug use. The substance is notably less caustic to nasal cavities than ethylphenidate but still causes mild to moderate damage with intranasal use; users should perform sterile saline nasal rinses after insufflation.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 5-10mg | 10-15mg | 15-30mg | 30mg+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Peak | Total |
|---|---|---|---|
| Oral | 10-25 min | 2-3 hrs | 5-6 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)
Stimulant
5.9
Strong
6/10
Strong anxiety/jitters and focus with moderate euphoria, mild stimulation
Stimulation / Energy
×3
5
stimulation
wakefulness
Euphoria / Mood Lift
×2
7
physical euphoria
cognitive euphoria
motivation enhancement
Focus / Productivity
×2
9
focus enhancement
analysis enhancement
thought acceleration
motivation enhancement
Anxiety / Jitters
×1
10
anxiety
increased heart rate
teeth grinding
vasoconstriction
Based on reports from:
Import into PsychonautWiki Journal
The PsychonautWiki Journal app includes 4F-EPH, but its built-in data can be thinner than ours. Importing this file adds a separate "4F-EPH (Substance Search)" custom substance with our dose ranges, durations and tolerance, so you can log against whichever you prefer.
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Import this file as custom substances
and you get "4F-EPH (Substance Search)" with every
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Android (v15+); the format is confirmed by the app's
developer.
Ranges are harm-reduction guidance, not a prescription.
Tolerance
Build-up
develops over days to weeks of regular use
Reset
3–7 days for acute tolerance; longer for full reset
Tolerance Decay
Full tolerance
1h
Half tolerance
10d
Baseline
~14d
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
Positive
- Stimulation
- Physical euphoria
Negative
- Pupil dilation
- Vasoconstriction
- Increased heart rate
- Increased blood pressure
- Teeth grinding
- Temporary erectile dysfunction
- Spontaneous bodily sensations
- Nasal damage
- Stamina intensification
Positive
- Cognitive euphoria
- Focus enhancement
- Empathy, affection, and sociability enhancement
- Motivation enhancement
- Analysis enhancement
- Wakefulness
Negative
- Depression
- Anxiety
- Irritability
- Thought deceleration
- Cognitive fatigue
- Motivation depression
- Thought acceleration
- Focus intensification
Positive
- Increased music appreciation
- Increased libido
- Perception of bodily lightness
Negative
- Appetite suppression
- Dehydration
- Decreased libido
- Orgasm depression
- Light sensitivity
- Spontaneous physical sensations
Community Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, and Bluelight. 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 1 thread 1 neutral visit
4F-EPH's nerd page
Pharmacology, chemical data, effect profiles, and more
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Helpful Links
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