Drug interactions
Diethylpropion + Nortriptyline
Severity: Major
Diethylpropion and Nortriptyline: 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
Diethylpropion is a sympathomimetic anorectic whose effects can be unpredictably altered by tricyclic antidepressants. Hypertension, tachycardia and arrhythmia are possible.
What this interaction means in plain words
Diethylpropion and Nortriptyline 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
Tricyclic blockade of norepinephrine reuptake and altered neuronal uptake of indirect sympathomimetics.
What to do
Avoid combining where possible. If used, monitor blood pressure and heart rate closely.
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
- Nortriptyline 10 mg Film-coated Tablets - SmPC sections 4.3/4.5 (class statement: sympathomimetic agents; "Nortriptyline should not be given with sympathomimetic agents such as adrenaline, ephedrine, isoprenaline, noradrenaline, phenylephrine and phenylpropanolamine.") — electronic medicines compendium (UK SmPC)
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 Diethylpropion with Nortriptyline?
MediHelp rates the interaction as major. Diethylpropion and Nortriptyline 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. Diethylpropion is a sympathomimetic anorectic whose effects can be unpredictably altered by tricyclic antidepressants. Hypertension, tachycardia and arrhythmia are possible.
How serious is the interaction between Diethylpropion and Nortriptyline?
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 combining where possible. If used, monitor blood pressure and heart rate closely.
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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