Drug interactions
Chlorpromazine + Diphenoxylate-atropine
Severity: Moderate
Chlorpromazine and Diphenoxylate-atropine: 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
Chlorpromazine is sedating and strongly anticholinergic, so combined with diphenoxylate-atropine it can cause additive drowsiness and antimuscarinic effects such as urinary retention, constipation, ileus and confusion. Anticholinergics may also modestly reduce chlorpromazine absorption.
What this interaction means in plain words
Chlorpromazine and Diphenoxylate-atropine 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.
Chlorpromazine belongs to Central Nervous System; Diphenoxylate-atropine belongs to Gastrointestinal Tract.
Why it happens
Additive CNS depression and antimuscarinic effects, with possible reduced oral chlorpromazine absorption from slowed gut motility.
What to do
Monitor for sedation, constipation, urinary retention and confusion, especially in the elderly, and watch for reduced antipsychotic response.
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 Diphenoxylate-atropine
- Diphenoxylate-atropine + Isocarboxazid Contraindicated
- Diphenoxylate-atropine + Phenelzine Contraindicated
- Diphenoxylate-atropine + Tranylcypromine Contraindicated
- Alfentanil + Diphenoxylate-atropine Major
- Alvimopan + Diphenoxylate-atropine Major
- Amitriptyline + Diphenoxylate-atropine Major
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 Diphenoxylate-atropine?
MediHelp rates the interaction as moderate. Chlorpromazine and Diphenoxylate-atropine 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. Chlorpromazine is sedating and strongly anticholinergic, so combined with diphenoxylate-atropine it can cause additive drowsiness and antimuscarinic effects such as urinary retention, constipation, ileus and confusion. Anticholinergics may also modestly reduce chlorpromazine absorption.
How serious is the interaction between Chlorpromazine and Diphenoxylate-atropine?
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 sedation, constipation, urinary retention and confusion, especially in the elderly, and watch for reduced antipsychotic response.
What other medicines interact with Diphenoxylate-atropine?
MediHelp also lists interactions of Diphenoxylate-atropine with, for example, Isocarboxazid, Phenelzine, Tranylcypromine. The full list is on the Diphenoxylate-atropine page.
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