Drug interactions
Clonazepam + Phentermine
Severity: Minor
Clonazepam and Phentermine: 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 sympathomimetic stimulant and clonazepam a sedative, so they may partly offset each other's CNS effects. No clinically important interaction is well documented.
What this interaction means in plain words
Clonazepam and Phentermine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Clonazepam belongs to Central Nervous System; Phentermine belongs to Central Nervous System.
Why it happens
Opposing CNS effects; no established pharmacokinetic mechanism.
What to do
No dose change is generally required; monitor for altered sedation, anxiety or sleep disturbance.
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 Clonazepam
- Calcium / magnesium / potassium / sodium oxybates + Clonazepam Contraindicated
- Clonazepam + Sodium oxybate Contraindicated
- Alfentanil + Clonazepam Major
- Alprazolam + Clonazepam Major
- Amobarbital + Clonazepam Major
- Belladonna and opium + Clonazepam 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 Clonazepam with Phentermine?
MediHelp rates the interaction as minor. Clonazepam and Phentermine 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 sympathomimetic stimulant and clonazepam a sedative, so they may partly offset each other's CNS effects. No clinically important interaction is well documented.
How serious is the interaction between Clonazepam and Phentermine?
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 generally required; monitor for altered sedation, anxiety or sleep disturbance.
What other medicines interact with Clonazepam?
MediHelp also lists interactions of Clonazepam with, for example, Calcium / magnesium / potassium / sodium oxybates, Sodium oxybate, Alfentanil. The full list is on the Clonazepam page.
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