Drug interactions
Hydroxyzine + Olanzapine / samidorphan
Severity: Moderate
Hydroxyzine and Olanzapine / samidorphan: 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
Both hydroxyzine and olanzapine have anticholinergic and sedating properties. Together they may increase constipation, urinary retention, confusion and drowsiness, and in severe cases cause serious gastrointestinal hypomotility.
What this interaction means in plain words
Hydroxyzine and Olanzapine / samidorphan 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.
Why it happens
Additive antimuscarinic and CNS depressant effects, with additive QT effects possible.
What to do
Monitor bowel function, sedation and anticholinergic symptoms; reduce hydroxyzine dose or use a non-anticholinergic alternative if symptoms develop.
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 Hydroxyzine
- Droperidol + Hydroxyzine Contraindicated
- Hydroxyzine + Pimozide Contraindicated
- Hydroxyzine + Thioridazine Contraindicated
- Hydroxyzine + Vandetanib Contraindicated
- Alfentanil + Hydroxyzine Major
- Amiodarone + Hydroxyzine Major
Frequently asked questions
Can I take Hydroxyzine with Olanzapine / samidorphan?
MediHelp rates the interaction as moderate. Hydroxyzine and Olanzapine / samidorphan 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. Both hydroxyzine and olanzapine have anticholinergic and sedating properties. Together they may increase constipation, urinary retention, confusion and drowsiness, and in severe cases cause serious gastrointestinal hypomotility.
How serious is the interaction between Hydroxyzine and Olanzapine / samidorphan?
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 bowel function, sedation and anticholinergic symptoms; reduce hydroxyzine dose or use a non-anticholinergic alternative if symptoms develop.
What other medicines interact with Hydroxyzine?
MediHelp also lists interactions of Hydroxyzine with, for example, Droperidol, Pimozide, Thioridazine. The full list is on the Hydroxyzine page.
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