Drug interactions
Atomoxetine + Protriptyline
Severity: Major
Atomoxetine and Protriptyline: major interaction.
Last updated Sources: UK SmPC
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
Protriptyline is a tricyclic antidepressant that can prolong QT, raise heart rate and increase blood pressure, and atomoxetine has similar noradrenergic effects. Combined use may increase cardiovascular toxicity, and CYP2D6 competition may also increase exposure to both drugs.
What this interaction means in plain words
Atomoxetine and Protriptyline 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.
Why it happens
Additive noradrenergic and QT-prolonging effects, with possible CYP2D6 competition.
What to do
Avoid the combination where possible; if needed, monitor ECG, heart rate and blood pressure and use low doses.
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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References
Other interactions of Atomoxetine
- Atomoxetine + Isocarboxazid Contraindicated
- Atomoxetine + Linezolid Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Atomoxetine + Procarbazine Contraindicated
- Atomoxetine + Rasagiline Contraindicated
- Atomoxetine + Selegiline Contraindicated
Frequently asked questions
Can I take Atomoxetine with Protriptyline?
MediHelp rates the interaction as major. Atomoxetine and Protriptyline 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. Protriptyline is a tricyclic antidepressant that can prolong QT, raise heart rate and increase blood pressure, and atomoxetine has similar noradrenergic effects. Combined use may increase cardiovascular toxicity, and CYP2D6 competition may also increase exposure to both drugs.
How serious is the interaction between Atomoxetine and Protriptyline?
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 where possible; if needed, monitor ECG, heart rate and blood pressure and use low doses.
What other medicines interact with Atomoxetine?
MediHelp also lists interactions of Atomoxetine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Atomoxetine page.
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