Carfentanil
Limited data
Limited data
Sparse data. Doses and effects may be unreliable or untested.
- 1 source
- duration data present
- 1 source
- duration data present
Aliases: Carfentanyl, Wildnil, R-33799, 4-methoxycarbonylfentanyl
Summary
Carfentanil is an ultra-potent synthetic opioid of the 4-anilidopiperidine class, estimated at roughly 10,000x the potency of morphine and ~100x that of fentanyl. It has NO recognised human therapeutic or recreational dose — it is used in veterinary medicine to immobilise large animals (brand name Wildnil). Microgram-level exposure can cause fatal respiratory depression. Carfentanil is increasingly found as an adulterant or substitute in the illicit opioid supply (often pressed into counterfeit pills or mixed into heroin/fentanyl), so exposure is frequently unintentional. Treat any suspected exposure as a medical emergency: give naloxone (repeated/large doses are often required), call emergency services, and monitor for prolonged or recurrent respiratory depression.
Dose Information
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset |
|---|---|---|---|
| Oral | Seconds to minutes | Minutes | - |
| Insufflated | Seconds to minutes | Minutes | - |
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 sedation and itching/nausea with mild pain relief
Tolerance
Cross-Tolerances
Effects
- Analgesia
- Respiratory depression
- Unconsciousness
- Nausea
- Vomiting
- Profound sedation
- Pinpoint pupils
- Sedation
Helpful Links
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