Drug lookup
Drug reference

levorphanol

Opioid agonist (morphinan) · Analgesic

Opioid agonist (morphinan)Analgesic
CDSCO approved
EXCRETION
not curated
INTERACTIONS
12 major
SEVERE in our sources
PREGNANCY
not curated
Top interactionssee all 12
  • AlprazolamSevereDatabaseDDInter
  • AlvimopanSevereDatabaseDDInter
  • AmobarbitalSevereDatabaseDDInter
  • AripiprazoleSevereDatabaseDDInter

Mechanism

Levorphanol's pharmacological effects closely parallel those of morphine, acting as an opioid agonist. The d-isomer, dextrorphan, has inhibitory effects at NMDA receptors but no analgesic action.

Indications

analgesia

Dosing

Adult
Oral: 4 mg/6–8 h; Parenteral: 2 mg/6–8 h
Pediatric
Oral: 0.04 mg/kg/6–8 h; Parenteral: 0.02 mg/kg/6–8 h

Pharmacokinetics

Half-life
12–16 h (long elimination half-life)
Metabolism
Metabolized less rapidly than morphine

Side effects

Common
nausea (less than morphine)vomiting (less than morphine)
Serious
  • accumulation (with repeated administration at short intervals)

Drug interactions

Alprazolam
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Alvimopan
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Amobarbital
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Aripiprazole
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Asenapine
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Baclofen
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Benzhydrocodone
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Brexpiprazole
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Buprenorphine
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Bupropion
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Buspirone
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Butabarbital
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Related guidelines

Ask House about levorphanol

Continue into a citation-backed clinical answer with the drug context already attached.

Sources: Goodman & Gilman 14e·Verified: 2026-05-10 · House clinical team