Drug interactions
Ofloxacin + Trimethoprim
Severity: Minor
Ofloxacin 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
Both drugs have been associated with QT prolongation, although the evidence for trimethoprim is limited. The combined risk is probably small except in patients with other risk factors.
What this interaction means in plain words
Ofloxacin 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.
Ofloxacin belongs to Anti Bacterial; Trimethoprim belongs to Anti Bacterial.
Why it happens
Possible additive effects on cardiac repolarization; the contribution of trimethoprim is not well established.
What to do
No routine action is needed in low-risk patients. Check ECG and electrolytes, including potassium, in those with cardiac disease or other QT-prolonging drugs.
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 Ofloxacin
- Ofloxacin + Thioridazine Contraindicated
- Adagrasib + Ofloxacin Major
- Amiodarone + Ofloxacin Major
- Amisulpride + Ofloxacin Major
- Anagrelide + Ofloxacin Major
- Arsenic trioxide + Ofloxacin Major
Other interactions of Trimethoprim
Frequently asked questions
Can I take Ofloxacin with Trimethoprim?
MediHelp rates the interaction as minor. Ofloxacin 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. Both drugs have been associated with QT prolongation, although the evidence for trimethoprim is limited. The combined risk is probably small except in patients with other risk factors.
How serious is the interaction between Ofloxacin 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 is needed in low-risk patients. Check ECG and electrolytes, including potassium, in those with cardiac disease or other QT-prolonging drugs.
What other medicines interact with Ofloxacin?
MediHelp also lists interactions of Ofloxacin with, for example, Thioridazine, Adagrasib, Amiodarone. The full list is on the Ofloxacin page.
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