Drug interactions
Memantine-donepezil + Trimethoprim
Severity: Minor
Memantine-donepezil 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
Memantine and trimethoprim are both cationic drugs handled by renal tubular secretion, so they may compete for elimination. Trimethoprim may raise memantine levels, while trimethoprim effect is unlikely to change meaningfully.
What this interaction means in plain words
Memantine-donepezil 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.
Memantine-donepezil belongs to Central Nervous System; Trimethoprim belongs to Anti Bacterial.
Why it happens
Competition for renal tubular cationic transport between trimethoprim and memantine.
What to do
No routine change is needed; monitor for dizziness or confusion in elderly patients or those with renal impairment.
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 Memantine-donepezil
- Dronedarone + Memantine-donepezil Contraindicated
- Memantine-donepezil + Thioridazine Contraindicated
- Amantadine + Memantine-donepezil Major
- Amiodarone + Memantine-donepezil Major
- Amisulpride + Memantine-donepezil Major
- Amitriptyline + Memantine-donepezil Major
Other interactions of Trimethoprim
Frequently asked questions
Can I take Memantine-donepezil with Trimethoprim?
MediHelp rates the interaction as minor. Memantine-donepezil 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. Memantine and trimethoprim are both cationic drugs handled by renal tubular secretion, so they may compete for elimination. Trimethoprim may raise memantine levels, while trimethoprim effect is unlikely to change meaningfully.
How serious is the interaction between Memantine-donepezil 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 change is needed; monitor for dizziness or confusion in elderly patients or those with renal impairment.
What other medicines interact with Memantine-donepezil?
MediHelp also lists interactions of Memantine-donepezil with, for example, Dronedarone, Thioridazine, Amantadine. The full list is on the Memantine-donepezil page.
Full monographs, dosing and an interaction checker in the MediHelp app
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