Lofentanil Encyclopedic

Encyclopedic

Typical encyclopedia coverage. Cross-reference for important decisions.

2 corroborating sources

2 ROAs with full dose ladders

duration data present

29 combo interactions documented

classified Research-chemical

dose data not in PW/TripSit (unverifiable)

Aliases: R-32792, R-34995, 3-methyl-4-carbomethoxyfentanyl

Summary dose.wiki

Ordinary analytical balances cannot measure a non-lethal dose; volumetric dilution under inert atmosphere is essential. Naloxone may require large, repeated boluses because of lofentanil's long receptor residence time. This is one of the most potent opioids known, and has an extremely long duration of action compared to other fentanyl analogs.

Dose Information source varies by route

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
Intravenous	0.1-0.3µg	0.3-1µg	1-2µg	2µg+ (rapidly lethal)
Insufflated	0.2-0.6µg	0.6-1.5µg	1.5-3µg	3µg+

Light Common Strong Heavy

Sources· 1 of 2 ladders not identified

Intravenous

Dose ladder — Drugs.Wiki

Insufflated

Dose ladder — source not identified

☠ 2 µg+ intravenous Rapidly lethal

“The intravenous dose ladder itself carries the annotation: "2 ug+ (rapidly lethal)".” — community dose ladder

Onset, Duration & After-effects dose.wiki Drugs.Wiki

ROA	Onset	Peak	Offset	After Effects	Total
Intravenous	1-2 min	10-30 min	4-6 hrs	2-6 hrs	4.18-6.53 hrs
Insufflated	5-10 min	10-30 min	4-6 hrs	2-6 hrs	4.25-6.67 hrs

Tolerance

Build-up develops within days of regular use; analgesic tolerance faster than respiratory depression tolerance

Reset Falls quickly once you stop, at a rate you can't judge. After any break, treat your tolerance as gone.

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

μ‑opioid agonists (e.g., fentanyl, morphine)

κ‑opioid agonists

Effects dose.wiki

Positive

Negative

Neutral

Positive

Negative

Combinations

Cross-Check Lofentanil with another substance

Lofentanil's nerd page Pharmacology, chemical data, effect profiles, and more

→

Helpful Links

📖 dose.wiki

Add to PsychonautWiki Journal

The PsychonautWiki Journal logging app doesn't include every substance. To track Lofentanil there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:

⬇ Download import file Import this file as custom substances and you get "Lofentanil (Substance Search)" with every route's full dose ladder and timeline, no typing. Works on iOS and Android (v15+); the format is confirmed by the app's developer. The manual values below work for older versions.

Name

Lofentanil

Unit

µg

Description

Lofentanil
Source: SubstanceSearch (substancesearch.com)

Intravenous dose (µg): threshold 0.1 · light 0.1-0.3 · common 0.3-1 · strong 1-2 · heavy 2+ (rapidly lethal)
Insufflated dose (µg): threshold 0.2 · light 0.2-0.6 · common 0.6-1.5 · strong 1.5-3 · heavy 3+

Intravenous duration: onset 1-2m · peak 10-30m · offset 4-6h · total 4.18-6.53h · after-effects 2-6h
Insufflated duration: onset 5-10m · peak 10-30m · offset 4-6h · total 4.25-6.67h · 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 ~ 0.65 µg (Intravenous).

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.

Report an issue or suggest an edit

Spotted incorrect or dangerous information, have a correction, a new study, or a useful addition for Lofentanil? Let us know. Reports are reviewed by moderators — this is not posted publicly.

Lofentanil Encyclopedic Encyclopedic Typical encyclopedia coverage. Cross-reference for important decisions. 2 corroborating sources 2 ROAs with full dose ladders duration data present 29 combo interactions documented classified Research-chemical dose data not in PW/TripSit (unverifiable)