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. At least one documented case of serotonin syndrome after a single 40 mg dose has been reported. Start low, avoid redosing within 24 hours, and space sessions generously to minimize risk.
Also known as: P-fluoroethamphetamine, 4-fluoroethylamphetamine, Para-fluoroethamphetamine, 4-fluoroethamphetamine, P-fluoro-N-ethylamphetamine, P-FEA, 4-FNEA
Classification
Chemical: Amphetamine
Psychoactive: Entactogen
Psychoactive: Stimulant
Tag: Habit-Forming
Tag: Research-Chemical
Tag: Tentative
Effects
Stimulation
Pupil Dilation
Increased Perspiration
Teeth Grinding
Headache
Jaw Tension
Cognitive Euphoria
Empathy Affection And Sociability Enhancement
Anxiety
Wakefulness
Euphoria
Emotional Warmth
Increased Music Appreciation
Tactile Enhancement
Increased Libido
Light Sensitivity
Appetite Suppression
Dehydration
Routes of Administration
Oral
Dosage
Threshold: 15–25 mg
Light: 15-40 mg
Common: 40-100 mg
Strong: 100-150 mg
Heavy: 220+ mg
Duration
Onset: 0.33-0.75 h
Comeup: 0.5-1 h
Peak: 1-3 h
Offset: 1-2 h
After Effects: 1-12 h
Total Duration: 4-7 h
Insufflated
Dosage
Threshold: 10–20 mg
Light: 20–60 mg
Common: 60–120 mg
Strong: 120–180 mg
Heavy: 180+ mg
Duration
Onset: 0.08-0.25 h
Comeup: 0.25-0.5 h
Peak: 0.75-2 h
Offset: 1-2 h
After Effects: 1-12 h
Total Duration: 3-6 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.
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4-FEA - DrugsPRO sprievodca látky
4-FEA: 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. At least
