Drug interactions
Siponimod + Trimethoprim
Severity: Minor
Siponimod and Trimethoprim: 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
Trimethoprim may weakly inhibit CYP2C9, which could modestly raise siponimod levels. The effect is probably small.
What this interaction means in plain words
Siponimod and Trimethoprim have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Siponimod belongs to Central Nervous System; Trimethoprim belongs to Anti Bacterial.
Why it happens
Possible weak CYP2C9 inhibition reducing siponimod clearance.
What to do
No routine action; monitor heart rate and adverse effects in CYP2C9*2/*3 or *3/*3 patients.
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 Siponimod
- Cladribine + Siponimod Contraindicated
- Fingolimod + Siponimod Contraindicated
- Fluconazole + Siponimod Contraindicated
- Influenza virus vaccine quadrivalent intranasal + Siponimod Contraindicated
- Ponesimod + Siponimod Contraindicated
- Siponimod + Thioridazine Contraindicated
Other interactions of Trimethoprim
Frequently asked questions
Can I take Siponimod with Trimethoprim?
MediHelp rates the interaction as minor. Siponimod and Trimethoprim have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Trimethoprim may weakly inhibit CYP2C9, which could modestly raise siponimod levels. The effect is probably small.
How serious is the interaction between Siponimod and Trimethoprim?
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 routine action; monitor heart rate and adverse effects in CYP2C9*2/*3 or *3/*3 patients.
What other medicines interact with Siponimod?
MediHelp also lists interactions of Siponimod with, for example, Cladribine, Fingolimod, Fluconazole. The full list is on the Siponimod page.
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