Drug interactions
Diphenoxylate-atropine + Nortriptyline
Severity: Moderate
Diphenoxylate-atropine and Nortriptyline: 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
Nortriptyline has strong anticholinergic and sedative properties that add to the atropine and opioid effects of diphenoxylate-atropine. This can cause urinary retention, constipation or paralytic ileus, dry mouth, confusion and excess drowsiness, particularly in older patients.
What this interaction means in plain words
Diphenoxylate-atropine and Nortriptyline 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.
Diphenoxylate-atropine belongs to Gastrointestinal Tract; Nortriptyline belongs to Central Nervous System.
Why it happens
Additive anticholinergic effects (atropine plus tricyclic antimuscarinic activity) and additive CNS depression from the opioid component.
What to do
Monitor for urinary retention, constipation or ileus, and sedation, and use the lowest effective doses. Avoid prolonged use in older adults or in patients with abdominal distension.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Diphenoxylate-atropine and Nortriptyline, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Nortriptyline
- Disopyramide + Nortriptyline Contraindicated
- Dofetilide + Nortriptyline Contraindicated
- Dronedarone + Nortriptyline Contraindicated
- Ibutilide + Nortriptyline Contraindicated
- Isocarboxazid + Nortriptyline Contraindicated
- Methylene blue + Nortriptyline Contraindicated
Frequently asked questions
Can I take Diphenoxylate-atropine with Nortriptyline?
MediHelp rates the interaction as moderate. Diphenoxylate-atropine and Nortriptyline 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. Nortriptyline has strong anticholinergic and sedative properties that add to the atropine and opioid effects of diphenoxylate-atropine. This can cause urinary retention, constipation or paralytic ileus, dry mouth, confusion and excess drowsiness, particularly in older patients.
How serious is the interaction between Diphenoxylate-atropine and Nortriptyline?
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 urinary retention, constipation or ileus, and sedation, and use the lowest effective doses. Avoid prolonged use in older adults or in patients with abdominal distension.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
