4Cl-iBF
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- 3 ROAs with full dose ladders
- duration data present
- 19 combo interactions documented
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
- 3 corroborating sources
- 3 ROAs with full dose ladders
- duration data present
- 19 combo interactions documented
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
Aliases: P-chloro-isobutyrylfentanyl, Para-chloroisobutyrylfentanyl
Summary
Potency of 4Cl-iBF is not precisely established but in vitro binding suggests it is weaker than fentanyl yet far more potent than morphine - DO NOT eyeball powder; use a calibrated 0.1 mg (100 ug) scale or volumetric solution. Numerous post-mortem and seized-sample reports confirm involvement in fatal overdoses; naloxone reverses toxicity but may require repeated dosing because of longer half-life than naloxone. Strong histamine release and chest-wall rigidity have been described with analogous compounds.
Dose Information
Dose basis. The dose figures on this page are not clinical data. They are aggregated from community reports by a secondary source whose own notes state there is no human pharmacokinetic study behind them, and our internal audit flags this substance's dosing as unverifiable. Treat them as a rough orientation, not a safe range. This is a microgram-active opioid: a normal milligram scale cannot weigh a dose of it accurately, and a weighing error here is measured in lethal multiples rather than percentages. Volumetric dosing is the only defensible method, and batch-to-batch potency in the unregulated supply varies enormously. Assume full respiratory depression, keep naloxone to hand, never dose alone, and never combine with benzodiazepines, alcohol or other depressants.
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Insufflated | 20-40ยตg | 40-80ยตg | 80-150ยตg | 150ยตg+ |
| Sublingual | 30-60ยตg | 60-120ยตg | 120-200ยตg | 200ยตg+ |
| Intravenous | 10-25ยตg | 25-50ยตg | 50-100ยตg | 100ยตg+ |
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Insufflated | 2-5 min | 15-45 min | 1-2 hrs | 1.28-2.83 hrs |
| Sublingual | 5-15 min | 15-45 min | 1-2 hrs | 1.33-3 hrs |
| Intravenous | <1-1 min | 15-45 min | 1-2 hrs | 1.25-2.77 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, itching/nausea, and pain relief with low sedation
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track 4Cl-iBF there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
4Cl-iBF Source: SubstanceSearch (substancesearch.com) Insufflated dose (ยตg): threshold 10-20 ยท light 20-40 ยท common 40-80 ยท strong 80-150 ยท heavy 150+ Sublingual dose (ยตg): threshold 15-30 ยท light 30-60 ยท common 60-120 ยท strong 120-200 ยท heavy 200+ Intravenous dose (ยตg): threshold 5-10 ยท light 10-25 ยท common 25-50 ยท strong 50-100 ยท heavy 100+ Insufflated duration: onset 2-5m ยท peak 15-45m ยท offset 1-2h ยท total 1.28-2.83h ยท after-effects 2-6h Sublingual duration: onset 5-15m ยท peak 15-45m ยท offset 1-2h ยท total 1.33-3h ยท after-effects 2-6h Intravenous duration: onset <1-1m ยท peak 15-45m ยท offset 1-2h ยท total 1.25-2.77h ยท after-effects 2-6h 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 ~ 60 ยตg (Insufflated).
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 โ the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Opioid tolerance develops rapidly with frequent use and decays slowly over weeks. Exact timelines vary considerably; conservative spacing between sessions is strongly advised. Data are largely extrapolated from clinical opioid literature and community reports, not controlled studies on 4ClโiBF.
Cross-Tolerances
Effects
- Analgesia
- Anxiolysis
- Physical euphoria
- Pain relief
- Itching
- Nausea
- Respiratory depression
- Sedation
- Miosis
- Pupil constriction
- Euphoria
- Reduced anxiety
- Cognitive euphoria
- Anxiety suppression
- Mood lift
- Constipation
- Dizziness
- Compulsive redosing
- Motor control loss
- Physical autonomy
- Warmth
- Color enhancement
- Increased music appreciation
- Brightened colour
- Light sensitivity
- Appetite suppression
- Disinhibition
- Dehydration
- Dulled perception
- Drifting
Combinations
Cross-Check 4Cl-iBF with another substanceHelpful Links
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