Drug interactions
Cyclizine + Olanzapine
Severity: Moderate
Cyclizine 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
Both drugs are sedating and anticholinergic, so combined use can cause marked drowsiness, confusion, constipation, urinary retention and tachycardia. Cyclizine also has antiemetic effects that may oppose the dopamine-mediated effects of antipsychotic therapy in some settings, and the anticholinergic burden is a particular concern in older patients.
What this interaction means in plain words
Cyclizine 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.
Cyclizine belongs to Respiratory; Olanzapine belongs to Central Nervous System.
Why it happens
Additive H1 antihistaminic and antimuscarinic effects causing CNS depression and anticholinergic toxicity.
What to do
Monitor for oversedation and anticholinergic effects and use the lowest effective doses. Consider an antiemetic with less anticholinergic activity in elderly or high-risk 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 Olanzapine
Other interactions of Cyclizine
- Calcium / magnesium / potassium / sodium oxybates + Cyclizine Major
- Cyclizine + Henbane Major
- Cyclizine + Sodium oxybate Major
- Abobotulinumtoxina + Cyclizine Moderate
- Alfentanil + Cyclizine Moderate
- Alprazolam + Cyclizine Moderate
Frequently asked questions
Can I take Cyclizine with Olanzapine?
MediHelp rates the interaction as moderate. Cyclizine 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. Both drugs are sedating and anticholinergic, so combined use can cause marked drowsiness, confusion, constipation, urinary retention and tachycardia. Cyclizine also has antiemetic effects that may oppose the dopamine-mediated effects of antipsychotic therapy in some settings, and the anticholinergic burden is a particular concern in older patients.
How serious is the interaction between Cyclizine 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 for oversedation and anticholinergic effects and use the lowest effective doses. Consider an antiemetic with less anticholinergic activity in elderly or high-risk patients.
What other medicines interact with Olanzapine?
MediHelp also lists interactions of Olanzapine with, for example, Amisulpride, Amoxapine, Apomorphine. The full list is on the Olanzapine page.
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