Drug interactions
Fenfluramine + Fluphenazine
Severity: Moderate
Fenfluramine and Fluphenazine: 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
Fenfluramine has serotonergic and stimulant properties and can cause somnolence or, less often, other CNS effects, whereas fluphenazine is sedating and can influence cardiac conduction. Together, the net effects on sedation are unpredictable, and fenfluramine's serotonergic activity may increase the risk of serotonin toxicity or neuroleptic-type reactions in rare cases.
What this interaction means in plain words
Fenfluramine and Fluphenazine 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; Fluphenazine belongs to Central Nervous System.
Why it happens
Pharmacodynamic interaction involving opposing CNS effects and serotonergic and dopaminergic activity; the precise mechanism is not established.
What to do
Monitor for changes in sedation, mental status, heart rate and signs of serotonin toxicity. Adjust doses based on response.
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?
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Other interactions of Fluphenazine
- Arsenic trioxide + Fluphenazine Contraindicated
- Dofetilide + Fluphenazine Contraindicated
- Fluphenazine + Ibutilide Contraindicated
- Fluphenazine + Pimozide Contraindicated
- Adagrasib + Fluphenazine Major
- Alfentanil + Fluphenazine Major
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 Fluphenazine?
MediHelp rates the interaction as moderate. Fenfluramine and Fluphenazine 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 has serotonergic and stimulant properties and can cause somnolence or, less often, other CNS effects, whereas fluphenazine is sedating and can influence cardiac conduction. Together, the net effects on sedation are unpredictable, and fenfluramine's serotonergic activity may increase the risk of serotonin toxicity or neuroleptic-type reactions in rare cases.
How serious is the interaction between Fenfluramine and Fluphenazine?
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 for changes in sedation, mental status, heart rate and signs of serotonin toxicity. Adjust doses based on response.
What other medicines interact with Fluphenazine?
MediHelp also lists interactions of Fluphenazine with, for example, Arsenic trioxide, Dofetilide, Ibutilide. The full list is on the Fluphenazine page.
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