Drug interactions
Difenoxin + Isocarboxazid
Severity: Major
Difenoxin and Isocarboxazid: major 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
Difenoxin is an active metabolite of diphenoxylate, a meperidine-related opioid antidiarrheal. With MAOIs there is a risk of hypertensive crisis per labeling, as well as opioid toxicity and CNS depression.
What this interaction means in plain words
Difenoxin and Isocarboxazid can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Difenoxin belongs to Gastrointestinal Tract; Isocarboxazid belongs to Central Nervous System.
Why it happens
Opioid and possible serotonergic effects potentiated by MAO inhibition; the exact mechanism is not fully established.
What to do
Avoid the combination and use a non-opioid antidiarrheal approach. Do not start difenoxin within 14 days of stopping isocarboxazid.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Isocarboxazid
- 5-HTP + Isocarboxazid Contraindicated
- Amitriptyline + Isocarboxazid Contraindicated
- Amobarbital + Isocarboxazid Contraindicated
- Amoxapine + Isocarboxazid Contraindicated
- Apraclonidine + Isocarboxazid Contraindicated
- Atomoxetine + Isocarboxazid Contraindicated
Other interactions of Difenoxin
Frequently asked questions
Can I take Difenoxin with Isocarboxazid?
MediHelp rates the interaction as major. Difenoxin and Isocarboxazid can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Difenoxin is an active metabolite of diphenoxylate, a meperidine-related opioid antidiarrheal. With MAOIs there is a risk of hypertensive crisis per labeling, as well as opioid toxicity and CNS depression.
How serious is the interaction between Difenoxin and Isocarboxazid?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination and use a non-opioid antidiarrheal approach. Do not start difenoxin within 14 days of stopping isocarboxazid.
What other medicines interact with Isocarboxazid?
MediHelp also lists interactions of Isocarboxazid with, for example, 5-HTP, Amitriptyline, Amobarbital. The full list is on the Isocarboxazid page.
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