Drug interactions
Fenfluramine + Pseudoephedrine
Severity: Moderate
Fenfluramine and Pseudoephedrine: 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
Both drugs can influence adrenergic and serotonergic activity, and combined use may increase heart rate and blood pressure. Fenfluramine is also associated with valvular heart disease and pulmonary hypertension, so extra cardiovascular stress is undesirable.
What this interaction means in plain words
Fenfluramine and Pseudoephedrine 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.
Fenfluramine belongs to Central Nervous System; Pseudoephedrine belongs to Respiratory.
Why it happens
Additive sympathomimetic effects; fenfluramine releases serotonin and pseudoephedrine releases norepinephrine.
What to do
Monitor blood pressure and heart rate, and review cardiac status per fenfluramine monitoring requirements. Prefer a non-sympathomimetic decongestant.
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 Fenfluramine and Pseudoephedrine, 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 14 days on the web. No card needed.
Other interactions of Pseudoephedrine
- Isocarboxazid + Pseudoephedrine Contraindicated
- Phenelzine + Pseudoephedrine Contraindicated
- Pseudoephedrine + Rasagiline Contraindicated
- Pseudoephedrine + Selegiline Contraindicated
- Pseudoephedrine + Selegiline transdermal Contraindicated
- Pseudoephedrine + Tranylcypromine Contraindicated
Other interactions of Fenfluramine
- Fenfluramine + Isocarboxazid Contraindicated
- Fenfluramine + Linezolid Contraindicated
- Fenfluramine + Phenelzine Contraindicated
- Fenfluramine + Selegiline Contraindicated
- Fenfluramine + Tranylcypromine Contraindicated
- Almotriptan + Fenfluramine Major
Frequently asked questions
Can I take Fenfluramine with Pseudoephedrine?
MediHelp rates the interaction as moderate. Fenfluramine and Pseudoephedrine 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. Both drugs can influence adrenergic and serotonergic activity, and combined use may increase heart rate and blood pressure. Fenfluramine is also associated with valvular heart disease and pulmonary hypertension, so extra cardiovascular stress is undesirable.
How serious is the interaction between Fenfluramine and Pseudoephedrine?
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 blood pressure and heart rate, and review cardiac status per fenfluramine monitoring requirements. Prefer a non-sympathomimetic decongestant.
What other medicines interact with Pseudoephedrine?
MediHelp also lists interactions of Pseudoephedrine with, for example, Isocarboxazid, Phenelzine, Rasagiline. The full list is on the Pseudoephedrine 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.
