Drug interactions
Morphine + Olanzapine
Severity: Moderate
Morphine and Olanzapine: moderate interaction.
Last updated
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
Olanzapine is sedating and can cause orthostatic hypotension, so combined with morphine it increases CNS depression and fall risk. Parenteral olanzapine combined with opioids or benzodiazepines has raised cardiorespiratory concerns.
What this interaction means in plain words
Morphine and Olanzapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Morphine belongs to Musculoskeletal; Olanzapine belongs to Central Nervous System.
Why it happens
Additive CNS depressant and hypotensive effects.
What to do
Monitor sedation, blood pressure and respiratory rate, particularly after dose increases or with injectable olanzapine. Start with reduced doses in elderly or frail patients.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Morphine
- Alvimopan + Morphine Contraindicated
- Isocarboxazid + Morphine Contraindicated
- Morphine + Olanzapine / samidorphan Contraindicated
- Morphine + Phenelzine Contraindicated
- Morphine + Tranylcypromine Contraindicated
- Alfentanil + Morphine Major
Other interactions of Olanzapine
Frequently asked questions
Can I take Morphine with Olanzapine?
MediHelp rates the interaction as moderate. Morphine and Olanzapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Olanzapine is sedating and can cause orthostatic hypotension, so combined with morphine it increases CNS depression and fall risk. Parenteral olanzapine combined with opioids or benzodiazepines has raised cardiorespiratory concerns.
How serious is the interaction between Morphine and Olanzapine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor sedation, blood pressure and respiratory rate, particularly after dose increases or with injectable olanzapine. Start with reduced doses in elderly or frail patients.
What other medicines interact with Morphine?
MediHelp also lists interactions of Morphine with, for example, Alvimopan, Isocarboxazid, Olanzapine / samidorphan. The full list is on the Morphine page.
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