Drug interactions
Nortriptyline + Perphenazine
Severity: Major
Nortriptyline and Perphenazine: 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
Both drugs can prolong the QT interval, and perphenazine inhibits CYP2D6 and may raise nortriptyline levels. The combination increases arrhythmia, sedation and anticholinergic burden.
What this interaction means in plain words
Nortriptyline and Perphenazine 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.
Nortriptyline belongs to Central Nervous System; Perphenazine belongs to Central Nervous System.
Why it happens
Additive QT prolongation with perphenazine inhibition of CYP2D6-mediated nortriptyline clearance.
What to do
Check ECG and electrolytes, and consider nortriptyline plasma level monitoring. Reduce the tricyclic dose if toxicity appears.
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 Nortriptyline
- Disopyramide + Nortriptyline Contraindicated
- Dofetilide + Nortriptyline Contraindicated
- Dronedarone + Nortriptyline Contraindicated
- Ibutilide + Nortriptyline Contraindicated
- Isocarboxazid + Nortriptyline Contraindicated
- Methylene blue + Nortriptyline Contraindicated
Other interactions of Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Frequently asked questions
Can I take Nortriptyline with Perphenazine?
MediHelp rates the interaction as major. Nortriptyline and Perphenazine 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. Both drugs can prolong the QT interval, and perphenazine inhibits CYP2D6 and may raise nortriptyline levels. The combination increases arrhythmia, sedation and anticholinergic burden.
How serious is the interaction between Nortriptyline and Perphenazine?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check ECG and electrolytes, and consider nortriptyline plasma level monitoring. Reduce the tricyclic dose if toxicity appears.
What other medicines interact with Nortriptyline?
MediHelp also lists interactions of Nortriptyline with, for example, Disopyramide, Dofetilide, Dronedarone. The full list is on the Nortriptyline page.
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