Drug interactions
Phentermine + Topiramate
Severity: Minor
Phentermine and Topiramate: 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 and topiramate are used together as a fixed-dose combination for weight management. They are not known to interact adversely, and the combination's adverse effects such as paresthesia, insomnia and cognitive effects are those of the individual drugs.
What this interaction means in plain words
Phentermine and Topiramate 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; Topiramate belongs to Central Nervous System.
Why it happens
No clinically significant interaction; pharmacokinetic effects between the two are minimal.
What to do
No dose change is needed. Monitor heart rate, mood and cognitive effects, and ensure effective contraception in women of childbearing potential.
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 Topiramate
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 Topiramate?
MediHelp rates the interaction as minor. Phentermine and Topiramate 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 and topiramate are used together as a fixed-dose combination for weight management. They are not known to interact adversely, and the combination's adverse effects such as paresthesia, insomnia and cognitive effects are those of the individual drugs.
How serious is the interaction between Phentermine and Topiramate?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No dose change is needed. Monitor heart rate, mood and cognitive effects, and ensure effective contraception in women of childbearing potential.
What other medicines interact with Topiramate?
MediHelp also lists interactions of Topiramate with, for example, Benzhydrocodone / acetaminophen, Buprenorphine long-acting, Buprenorphine subdermal implant. The full list is on the Topiramate page.
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