Levomethorphan
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 1 source
- 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)
- 1 source
- 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
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 2-5mg | 5-10mg | 10-15mg | 10mg+ |
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Oral | 20-60 min | 1-3 hrs | 4-6 hrs | 4-8 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
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
- Cognitive Euphoria
- Compulsive redosing
- Dysphoria
- Constipation
- Dizziness
- Dissociation
- Visual geometry
- Appetite suppression
- Decreased Libido
- Appetite Suppression
- Double vision
- Spatial disorientation
- Dulled perception
- Internal hallucination
- Internal hallucinations
- Visual and auditory hallucinations
Combinations
Cross-Check Levomethorphan with another substanceHelpful Links
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