Drug interactions
Clozapine + Cyclizine
Severity: Moderate
Clozapine and Cyclizine: 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
Cyclizine is a sedating antihistamine with anticholinergic activity, so combining it with clozapine increases drowsiness and anticholinergic effects. This raises the risk of constipation, ileus, urinary retention and tachycardia. Clozapine-related gastrointestinal hypomotility can be dangerous.
What this interaction means in plain words
Clozapine and Cyclizine 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.
Clozapine belongs to Central Nervous System; Cyclizine belongs to Respiratory.
Why it happens
Additive sedative (H1) and antimuscarinic pharmacodynamic effects.
What to do
Monitor sedation, bowel function and heart rate, and use the lowest effective cyclizine dose for the shortest time. Consider an antiemetic with less anticholinergic activity if the combination is poorly tolerated.
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 Clozapine
- Clozapine + Deferiprone Contraindicated
- Clozapine + Irinotecan Contraindicated
- Clozapine + Pimozide Contraindicated
- Clozapine + Thioridazine Contraindicated
- Acalabrutinib + Clozapine Major
- Adagrasib + Clozapine Major
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 Clozapine with Cyclizine?
MediHelp rates the interaction as moderate. Clozapine and Cyclizine 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 is a sedating antihistamine with anticholinergic activity, so combining it with clozapine increases drowsiness and anticholinergic effects. This raises the risk of constipation, ileus, urinary retention and tachycardia. Clozapine-related gastrointestinal hypomotility can be dangerous.
How serious is the interaction between Clozapine and Cyclizine?
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, bowel function and heart rate, and use the lowest effective cyclizine dose for the shortest time. Consider an antiemetic with less anticholinergic activity if the combination is poorly tolerated.
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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