Drug interactions
Amoxapine + Olanzapine
Severity: Major
Amoxapine and Olanzapine: major 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
Amoxapine has dopamine-blocking activity from its metabolite, so combining it with olanzapine increases the risk of extrapyramidal symptoms, neuroleptic malignant syndrome, sedation and QT prolongation. Anticholinergic effects and seizure risk may also add.
What this interaction means in plain words
Amoxapine and Olanzapine 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 dopamine D2 antagonism, CNS depression, anticholinergic and QT-prolonging effects.
What to do
Avoid if possible; if combined, monitor for rigidity, hyperthermia, movement disorders, sedation and ECG changes. Use the lowest effective doses and correct electrolyte abnormalities.
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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Other interactions of Olanzapine
Frequently asked questions
Can I take Amoxapine with Olanzapine?
MediHelp rates the interaction as major. Amoxapine and Olanzapine 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. Amoxapine has dopamine-blocking activity from its metabolite, so combining it with olanzapine increases the risk of extrapyramidal symptoms, neuroleptic malignant syndrome, sedation and QT prolongation. Anticholinergic effects and seizure risk may also add.
How serious is the interaction between Amoxapine and Olanzapine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible; if combined, monitor for rigidity, hyperthermia, movement disorders, sedation and ECG changes. Use the lowest effective doses and correct electrolyte abnormalities.
What other medicines interact with Olanzapine?
MediHelp also lists interactions of Olanzapine with, for example, Amisulpride, Apomorphine, Arsenic trioxide. The full list is on the Olanzapine page.
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