Levorphanol and Butorphanol Nasal Spray: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Levorphanol
Butorphanol Nasal Spray
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Reduced analgesic effect or precipitation of withdrawal symptoms, and an increased risk of serotonin syndrome
Interaction Deep Dive
Avoid concomitant use of levorphanol with a mixed opioid agonist/antagonist or a partial agonist opioid analgesic as this may reduce the analgesic effect of levorphanol and may precipitate withdrawal symptoms. Additionally, observe the patient carefully when using levorphanol concomitantly with other drugs that affect the serotonergic system, especially during initiation and titration, as risk for serotonin syndrome is increased; discontinue if suspected1.
Why it happens (mechanism)
Opioid receptor antagonism; additive serotonergic effects
Common questions
Can I take Levorphanol and Butorphanol Nasal Spray together?
Reduced analgesic effect or precipitation of withdrawal symptoms, and an increased risk of serotonin syndrome Always confirm with your pharmacist or prescriber before making any change.
How serious is the Levorphanol and Butorphanol Nasal Spray interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Levorphanol or Butorphanol Nasal Spray need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: levorphanol tartrate oral tablets, levorphanol tartrate oral tablets. Sentynl Therapeutics Inc (per DailyMed), Solana Beach, CA, 2016. DailyMed
Keep reading about Levorphanol
Keep reading about Butorphanol Nasal Spray
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