Drug interactions
Clozapine + Levorphanol
Severity: Major
Clozapine and Levorphanol: major interaction.
Last updated Sources: UK SmPC
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Clozapine and the opioid levorphanol both depress the central nervous system. Combined use can cause excess sedation, hypotension and respiratory depression, and clozapine itself carries risks of orthostasis and respiratory or circulatory collapse.
What this interaction means in plain words
Clozapine and Levorphanol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Additive CNS and respiratory depression, with additive hypotensive effects.
What to do
Use the lowest effective opioid dose and titrate slowly, monitoring sedation, blood pressure and respiratory rate. Avoid other CNS depressants and counsel patients about driving and alcohol.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
Other interactions of Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
Frequently asked questions
Can I take Clozapine with Levorphanol?
MediHelp rates the interaction as major. Clozapine and Levorphanol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Clozapine and the opioid levorphanol both depress the central nervous system. Combined use can cause excess sedation, hypotension and respiratory depression, and clozapine itself carries risks of orthostasis and respiratory or circulatory collapse.
How serious is the interaction between Clozapine and Levorphanol?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lowest effective opioid dose and titrate slowly, monitoring sedation, blood pressure and respiratory rate. Avoid other CNS depressants and counsel patients about driving and alcohol.
What other medicines interact with Clozapine?
MediHelp also lists interactions of Clozapine with, for example, Deferiprone, Irinotecan, Pimozide. The full list is on the Clozapine page.
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