Ofloxacin and Tizanidine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Tizanidine
No brand names on recordOfloxacin
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased tizanidine plasma concentrations
Interaction Deep Dive
Tizanidine, a centrally acting skeletal muscle relaxant and an alpha-2 adrenergic agonist with blood pressure lowering effects, is primarily metabolized by the CYP1A2 isozyme. Although not studied, coadministration with ofloxacin, a CYP1A2 inhibitor, should be avoided due to the possibility of increased tizanidine exposure, which may result in excessive sedation and hypotension. However, if concomitant use of ofloxacin and tizanidine is deemed necessary, caution is advised1. An alternative for the management of spasticity should be considered. If tizanidine is coadministered with ofloxacin, monitor for signs and symptoms of hypotension.
Why it happens (mechanism)
Inhibition of CYP1A2-mediated tizanidine metabolism
Common questions
Can I take Ofloxacin and Tizanidine together?
Increased tizanidine plasma concentrations Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ofloxacin and Tizanidine interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Ofloxacin or Tizanidine need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: ZANAFLEX CAPSULES(TM) oral capsules, tizanidine hcl oral capsules. Acorda Therapeutics, Hawthorne, NY, 2006. DailyMed
Keep reading about Tizanidine
Keep reading about Ofloxacin
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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