Drug interactions
Chlorpromazine + Orphenadrine
Severity: Moderate
Chlorpromazine and Orphenadrine: 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 may cause drowsiness, confusion, dry mouth, urinary retention and constipation. Older patients are at greatest risk of delirium and falls. Reports also describe reduced phenothiazine effect with orphenadrine.
What this interaction means in plain words
Chlorpromazine and Orphenadrine 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 CNS depression and antimuscarinic effects.
What to do
Monitor for oversedation and anticholinergic toxicity, and avoid or minimize the combination in elderly patients. Reduce the dose if adverse effects appear.
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 Chlorpromazine
- Chlorpromazine + Dofetilide Contraindicated
- Chlorpromazine + Dronedarone Contraindicated
- Chlorpromazine + Droperidol Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Chlorpromazine + Metrizamide Contraindicated
- Chlorpromazine + Panobinostat Contraindicated
Frequently asked questions
Can I take Chlorpromazine with Orphenadrine?
MediHelp rates the interaction as moderate. Chlorpromazine and Orphenadrine 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 may cause drowsiness, confusion, dry mouth, urinary retention and constipation. Older patients are at greatest risk of delirium and falls. Reports also describe reduced phenothiazine effect with orphenadrine.
How serious is the interaction between Chlorpromazine and Orphenadrine?
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 toxicity, and avoid or minimize the combination in elderly patients. Reduce the dose if adverse effects appear.
What other medicines interact with Chlorpromazine?
MediHelp also lists interactions of Chlorpromazine with, for example, Dofetilide, Dronedarone, Droperidol. The full list is on the Chlorpromazine page.
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