Drug interactions
Caffeine + Fenfluramine
Severity: Minor
Caffeine and Fenfluramine: minor 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 can cause insomnia, anxiety and decreased appetite, and caffeine as a stimulant may worsen insomnia and agitation. Fenfluramine can also cause sedation in some patients, which caffeine may partly offset.
What this interaction means in plain words
Caffeine and Fenfluramine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Caffeine belongs to Miscellaneous; Fenfluramine belongs to Central Nervous System.
Why it happens
Overlapping CNS effects; no established pharmacokinetic interaction.
What to do
Advise moderating caffeine, particularly in the evening, and monitor sleep, mood and heart rate.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Caffeine
- Caffeine + Ephedrine Major
- Caffeine + Fezolinetant Major
- Caffeine + Methylenedioxymethamphetamine Major
- Caffeine + Selegiline transdermal Major
- Adenosine + Caffeine Moderate
- Benzphetamine + Caffeine Moderate
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 Caffeine with Fenfluramine?
MediHelp rates the interaction as minor. Caffeine and Fenfluramine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Fenfluramine can cause insomnia, anxiety and decreased appetite, and caffeine as a stimulant may worsen insomnia and agitation. Fenfluramine can also cause sedation in some patients, which caffeine may partly offset.
How serious is the interaction between Caffeine and Fenfluramine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise moderating caffeine, particularly in the evening, and monitor sleep, mood and heart rate.
What other medicines interact with Caffeine?
MediHelp also lists interactions of Caffeine with, for example, Ephedrine, Fezolinetant, Methylenedioxymethamphetamine. The full list is on the Caffeine page.
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