Levomethorphan
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 2 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
- 2 corroborating sources
- 1 ROA with full dose ladder
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
- classified Research-chemical
- dose data not in PW/TripSit (unverifiable)
Aliases: Lvm, Ro 1-5470/6, L-methorphan
Summary
Levomethorphan is a potent opioid analgesic that has never been marketed pharmaceutically. It is the L-stereoisomer of racemethorphan and acts as a prodrug to levorphanol, being demethylated by liver enzymes to its active form. Approximately five times more potent than morphine, levomethorphan carries significant risks of respiratory depression, addiction, and overdose.
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. 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 |
|---|---|---|---|---|
| Oral | 2-5mg | 5-10mg | 10-15mg | 15mg+ |
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 20-60 min | 30-90 min | 1-3 hrs | 4-6 hrs | 5.83-11.5 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 Levomethorphan there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
Levomethorphan Source: SubstanceSearch (substancesearch.com) Oral dose (mg): threshold 1-2 Β· light 2-5 Β· common 5-10 Β· strong 10-15 Β· heavy 15+ Oral duration: onset 0.33-1h Β· come-up 0.5-1.5h Β· peak 1-3h Β· offset 4-6h Β· total 5.83-11.5h Β· after-effects 2-4h 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 ~ 7.5 mg (Oral).
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
Opioid tolerance develops rapidly with repeated use and decays over weeks. Crossβtolerance exists across ΞΌβagonist opioids; loss of tolerance after a break substantially increases overdose risk at previously tolerated doses.
Effects
- Pain relief
- Physical euphoria
- Analgesia
- Respiratory depression
- Itching
- Nausea
- Dry Mouth
- Sedation
- Itchiness
- Relaxant
- Euphoria
- Cognitive euphoria
- Anxiety suppression
- Mood lift
- Compulsive redosing
- Dysphoria
- Constipation
- Dizziness
- Dissociation
- Visual geometry
- Appetite suppression
- Decreased Libido
- Double vision
- Spatial disorientation
- Dulled perception
- Internal hallucination
- Internal hallucinations
- Visual and auditory hallucinations
Combinations
Cross-Check Levomethorphan with another substanceHelpful Links
Report an issue or suggest an edit
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