Drug interactions
Phentermine + Quetiapine
Severity: Minor
Phentermine and Quetiapine: 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
Phentermine is a stimulant that may counteract quetiapine sedation, and it can raise heart rate and blood pressure. Stimulants may also aggravate psychotic symptoms, so the net effect is unpredictable.
What this interaction means in plain words
Phentermine and Quetiapine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Phentermine belongs to Central Nervous System; Quetiapine belongs to Central Nervous System.
Why it happens
Opposing CNS stimulation and sedation; no well-defined mechanism.
What to do
Monitor mental status, heart rate and blood pressure. Reconsider phentermine if psychiatric symptoms worsen.
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 Quetiapine
- Adagrasib + Quetiapine Major
- Amiodarone + Quetiapine Major
- Amisulpride + Quetiapine Major
- Amoxapine + Quetiapine Major
- Anagrelide + Quetiapine Major
- Apalutamide + Quetiapine Major
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 Phentermine with Quetiapine?
MediHelp rates the interaction as minor. Phentermine and Quetiapine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Phentermine is a stimulant that may counteract quetiapine sedation, and it can raise heart rate and blood pressure. Stimulants may also aggravate psychotic symptoms, so the net effect is unpredictable.
How serious is the interaction between Phentermine and Quetiapine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor mental status, heart rate and blood pressure. Reconsider phentermine if psychiatric symptoms worsen.
What other medicines interact with Quetiapine?
MediHelp also lists interactions of Quetiapine with, for example, Adagrasib, Amiodarone, Amisulpride. The full list is on the Quetiapine page.
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