Remifentanil
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 1 source
- partial dose data
- duration data present
- 29 combo interactions documented
- PubChem toxicity data
- dose data not in PW/TripSit (unverifiable)
- 1 source
- partial dose data
- duration data present
- 29 combo interactions documented
- PubChem toxicity data
- dose data not in PW/TripSit (unverifiable)
Aliases: Ultiva
Summary
Standard anesthetic practice uses continuous infusions of 0.05-0.25 ug/kg/min; analgesia ceases within approximately 5 minutes of pump stoppage due to ester hydrolysis. Context-sensitive half-life is 2-4 minutes regardless of infusion length. Bolus dosing outside monitored settings is strongly discouraged because apnea can occur before the syringe is empty.
Dose Information
Dose basis. Remifentanil is given in clinical practice as a weight-indexed infusion — micrograms per kilogram per minute, titrated by an anaesthetist with airway support immediately available. The flat figures on this page are community-derived and are NOT the clinical dosing; the product label specifies no flat microgram dose at all. Treat them as orientation only. Outside a theatre setting this drug’s margin does not exist: onset is about a minute and apnoea is the expected effect, not a complication.
| ROA | Light | Heavy |
|---|---|---|
| Intravenous | 10-20ug | 100+ ug (dangerous) |
Sources· 1 of 1 ladders not fully identified
Intravenous
Dose ladder — Light: DrugsPRO · Heavy: not identifiedOnset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Intravenous | 1 min | 1-2 min | 3-5 min | 5-8 min |
Effect Profile
Scores (0–10) 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, low sedation
Tolerance
No tolerance chart. Our decay curves for opioids were estimates, and a curve can make tolerance look longer-lasting than it is, which is the dangerous direction.
Opioid tolerance drops fast when you stop, and even a few days off can be enough, so a dose that used to be normal can now stop your breathing. Overdose deaths rise sharply after prison, detox or leaving treatment, and tolerance also falls during a hospital stay. After any break, start with a much smaller amount, try a test dose first, don't use alone, and keep naloxone within reach. Alcohol, benzodiazepines, gabapentinoids and other sedatives make an opioid overdose much more likely.
Sources: FRANK: heroin · National Harm Reduction Coalition · WHO: opioid overdose · Merrall et al. 2010 · Binswanger et al. 2007 · Strang et al. 2003 · FDA 2019: gabapentinoids and breathing
Cross-Tolerances
Effects
Effect glossary — · full glossary
Combinations
Cross-Check Remifentanil with another substanceHelpful Links
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track Remifentanil there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
Remifentanil Source: SubstanceSearch (substancesearch.com) Intravenous dose (µg): threshold 5-10ug (slow IV push) · light 10-20ug · heavy 100+ ug (dangerous) Intravenous duration: onset 1m · peak 1-2m · offset 3-5m · total 5-8m · after-effects 5-15m Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
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.
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