Etonitazene
Limited data
Limited data
Sparse data. Doses and effects may be unreliable or untested.
- 1 source
- duration data present
- 19 combo interactions documented
- classified Research-chemical
- 1 source
- duration data present
- 19 combo interactions documented
- classified Research-chemical
Aliases: Ea-4941, Cs-4640
Summary
Etonitazene is an extremely potent synthetic opioid discovered in 1957, approximately 1,000-1,500 times stronger than morphine in animal studies but likely 60 times stronger in humans. It was never approved for medical use due to severe dependency potential and respiratory depression. Etonitazene has an unpredictably steep dose-response curve and erratic pharmacokinetics, especially when injected, making it more hazardous than fentanyl.
Dose Information
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset |
|---|---|---|---|---|
| Oral | 5-15 min | 15-30 min | 1-3 hrs | 2-4 hrs |
| Insufflated | 2-10 min | 10-20 min | 1-2 hrs | 1-3 hrs |
| Intravenous | 1 min | 2-5 min | 30 min | 1-2 hrs |
| Smoked | 1-3 min | 5-15 min | 30 min | 1-2 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 euphoria and pain relief with moderate itching/nausea, mild sedation
Tolerance
Tolerance Decay
Acute tolerance: develops within a single session โ the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Pattern approximated from general opioid tolerance behavior (rapid build with repeated dosing; partial decay over 1โ4 weeks) and mechanistic mu-receptor downregulation; specific etonitazene human data are lacking. Treat as a conservative harm-reduction estimate; individual variability is large.
Cross-Tolerances
Effects
- Physical euphoria
- Pain relief
- Muscle relaxation
- Analgesia
- Respiratory depression
- Nausea
- Sedation
- Difficulty urinating
- Itchiness
- Pupil constriction
- Cognitive euphoria
- Anxiety suppression
- Reduced anxiety
- Wakefulness
- Motivation enhancement
- Euphoria
- Compulsive redosing
- Constipation
- Motivation suppression
- Anxiety
- Warmth
- Increased music appreciation
- Increased libido
- Appetite suppression
- Light sensitivity
- Disinhibition
- Dehydration
- Dulled perception
- Internal hallucination
- Warm flush
Combinations
Cross-Check Etonitazene with another substanceHelpful Links
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