Drug interactions
Citalopram + Phentermine
Severity: Moderate
Citalopram and Phentermine: 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
Phentermine is a sympathomimetic amine with some monoamine-releasing activity, and combining it with an SSRI such as citalopram has been associated with a theoretical risk of serotonin syndrome. Reports are sparse and the interaction is largely predicted.
What this interaction means in plain words
Citalopram and Phentermine 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.
Citalopram belongs to Central Nervous System; Phentermine belongs to Central Nervous System.
Why it happens
Possible additive serotonergic and noradrenergic activity; the mechanism is not firmly established.
What to do
Monitor for symptoms of serotonin toxicity and raised blood pressure or heart rate, especially at initiation or after dose increases. Consider an alternative weight-loss agent if symptoms appear.
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 Citalopram
- Cisapride + Citalopram Contraindicated
- Citalopram + Dronedarone Contraindicated
- Citalopram + Escitalopram Contraindicated
- Citalopram + Isocarboxazid Contraindicated
- Citalopram + Methylene blue Contraindicated
- Citalopram + Phenelzine Contraindicated
Other interactions of Phentermine
- Isocarboxazid + Phentermine Contraindicated
- Linezolid + Phentermine Contraindicated
- Phenelzine + Phentermine Contraindicated
- Phentermine + Procarbazine Contraindicated
- Phentermine + Rasagiline Contraindicated
- Phentermine + Selegiline Contraindicated
Frequently asked questions
Can I take Citalopram with Phentermine?
MediHelp rates the interaction as moderate. Citalopram and Phentermine 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. Phentermine is a sympathomimetic amine with some monoamine-releasing activity, and combining it with an SSRI such as citalopram has been associated with a theoretical risk of serotonin syndrome. Reports are sparse and the interaction is largely predicted.
How serious is the interaction between Citalopram and Phentermine?
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 symptoms of serotonin toxicity and raised blood pressure or heart rate, especially at initiation or after dose increases. Consider an alternative weight-loss agent if symptoms appear.
What other medicines interact with Citalopram?
MediHelp also lists interactions of Citalopram with, for example, Cisapride, Dronedarone, Escitalopram. The full list is on the Citalopram page.
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