4-FEA
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 18 combo interactions documented
- classified Tentative
- classified Research-chemical
- 3 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 18 combo interactions documented
- classified Tentative
- classified Research-chemical
Aliases: P-fluoroethamphetamine, 4-fluoroethylamphetamine, Para-fluoroethamphetamine
Summary
4-FEA is the ethyl analogue of 4-FA with strong serotonergic properties. Limited formal pharmacological research exists; batch-to-batch variability is high. The compound is intensely serotonergic and may produce significant after-effects including headaches and cardiovascular strain.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 25-50mg | 50-75mg | 75-150mg | 150mg+ |
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 20-45 min | 30-60 min | 1-3 hrs | 1-2 hrs | 4-6 hrs |
| Insufflated | 5-15 min | 15-30 min | 1-2 hrs | 1-2 hrs | 4-6 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)
Moderate stimulation, sensory enhancement, and euphoria with low empathy
Strong anxiety/jitters with moderate euphoria and stimulation, low focus
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track 4-FEA there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
4-FEA Source: SubstanceSearch (substancesearch.com) Oral dose (mg): light 25-50 · common 50-75 · strong 75-150 · heavy 150+ Insufflated dose (mg): threshold 5 Oral duration: onset 20-45m · come-up 0.5-1h · peak 1-3h · offset 1-2h · total 4-6h · after-effects 1-12h Insufflated duration: onset 5-15m · come-up 15-30m · peak 1-2h · offset 1-2h · total 4-6h · after-effects 1-12h Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
Tip: for quicker logging you can also add a Custom Unit in the app, e.g. common dose ~ 62.5 mg (Oral).
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.
Extrapolated from MDMA/4‑FA user patterns: tolerance builds quickly with serotonergic releasers and decays over weeks. Leave several weeks to months between sessions to reduce tolerance and potential neurochemical stress. Data quality is anecdotal.
Cross-Tolerances
Effects
- Stimulation
- Pupil dilation
- Increased perspiration
- Teeth grinding
- Headaches
- Increased heart rate
- Vasoconstriction
- Insomnia
- Sweating
- Decreased appetite
- Cognitive euphoria
- Empathy, affection, and sociability enhancement
- Wakefulness
- Alertness enhancement
- Euphoria
- Motivation enhancement
- Anxiety
- Talkativeness
- Time distortion
- Thought acceleration
- Increased music appreciation
- Tactile enhancement
- Increased libido
- Tracers
- Color enhancement
- Pattern recognition enhancement
- Light sensitivity
- Dehydration
- Appetite suppression
- Disinhibition
Combinations
Cross-Check 4-FEA with another substanceHelpful Links
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