Last reviewed 2026-04-20 · How we verify

Levo-Dromoran (LEVORPHANOL)

Levorphanol binds primarily to mu-opioid receptors to produce analgesia, with no ceiling effect for pain relief.

Levo-Dromoran (Levorphanol) is a small molecule opioid agonist that targets the mu-type opioid receptor. Originally developed and currently owned by Valeant Pharm Intl, it was FDA-approved in 1953 for general anesthesia, local anesthesia, and pain management. As an off-patent medication, it is available from multiple generic manufacturers. Key safety considerations include its potential for dependence and abuse. Levo-Dromoran has a half-life of 13.5 hours.

At a glance

Mechanism of action

Levorphanol is a full opioid agonist that mainly targets mu-opioid receptors to provide pain relief. While it can also bind to other opioid receptors at higher doses, its primary therapeutic action is analgesia, which can be increased without a limit on effectiveness, though side effects may limit dosage.

Approved indications

• Severe Pain Management

Boxed warnings

• WARNING: SERIOUS AND LIFE-THREATENING RISKS FROM USE OF LEVORPHANOL TARTRATE TABLETS Addiction, Abuse, and Misuse Because the use of Levorphanol Tartrate Tablets exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death, assess each patient’s risk prior to prescribing and reassess all patients regularly for the development of these behaviors and conditions [see WARNINGS ]. Life-Threatening Respiratory Depression Serious, life-threatening, or fatal respiratory depression may occur with use of Levorphanol Tartrate Tablets, especially during initiation or following a dosage increase. To reduce the risk of respiratory depression, proper dosing and titration of Levorphanol Tartrate Tablets are essential [see WARNINGS ]. Accidental Ingestion Accidental ingestion of even one dose of Levorphanol Tartrate Tablets, especially by children, can result in a fatal overdose of levorphanol [see WARNINGS ]. Risks from Concomitant Use with Benzodiazepines or Other CNS Depressants Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of Levorphanol Tartrate Tablets and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate [see WARNINGS ] . Neonatal Opioid Withdrawal Syndrome (NOWS) If opioid use is required for an extended period of time in a pregnant woman, advise the patient of the risk of NOWS, which may be life-threatening if not recognized and treated. Ensure that management by neonatology experts will be available at delivery [see WARNINGS ] . Opioid Analgesic Risk Evaluation and Mitigation Strategy (REMS) Healthcare providers are strongly encouraged to complete a REMS-compliant education program and to counsel patients and caregivers on serious risks, safe use, and the importance of reading the Medication Guide with each prescription [see WARNINGS ].

Common side effects

• Serotonin syndrome
• Adrenal insufficiency
• Anaphylaxis
• Androgen deficiency
• Hyperalgesia and Allodynia
• Cardiac arrest
• Shock
• Kidney failure
• Suicide attempt
• Coma
• Convulsions
• Apnea

Drug interactions

• naltrexone

Key clinical trials

• Levorphanol as a Second Line Opioid in Reducing Pain in Patients With Cancer (EARLY_PHASE1)
• Evolution of Analgesic Tolerance With Opioids (NA)

Primary sources

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