Furanylfentanyl
Aliases: Fu-f, furanyl-fentanyl
Summary
Furanylfentanyl (Fu-F) is a potent ฮผ-opioid full agonist approximately 50-100 times more potent than morphine and roughly half as potent as fentanyl. U.S. and EU regulators placed it in Schedule I after at least 23 confirmed deaths in Europe alone by 2017. It exhibits rapid-onset but short-lived euphoria and profound respiratory depression.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Insufflated | 200-400ug | 400-800ug | 800-1600ug | 1600ug+ |
| Oral | 300-500ug | 500-900ug | 900-1600ug+ | 1600ug++ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Insufflated | 1-5 min | 15-30 min | 1-2 hrs | 1.3-2.6 hrs |
| Oral | 1-10 min | 1-3 hrs | - | 1-3.2 hrs |
Effect Profile
3 reportsScores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Weighted by importance: core (×3), major (×2), minor (×1)
Opioid
7.0
Strong+
7/10
Strong euphoria, itching/nausea, and pain relief with low sedation
Euphoria / Warmth
×3
10
physical euphoria
cognitive euphoria
euphoria
warmth
mood lift
Analgesia
×2
8
analgesia
pain relief
Sedation / Relaxation
×1
3
sedation
Itching / Nausea
×1
10
itching
nausea
constipation
Based on reports from:
Tolerance
Build-up
develops within days of regular use; analgesic tolerance faster than respiratory depression tolerance
Reset
7โ14 days for partial reset; full reset may take weeks โ tolerance loss greatly increases overdose risk
Cross-Tolerances
opioids
60%
Effects
Aggregated from 3 Erowid experience reports
Positive Effects 1
Anxiety Suppression
100.0%
70%
Adverse Effects 0
Combinations
Furanylfentanyl's nerd page
Pharmacology, chemical data, effect profiles, and more
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