Fluvoxamine and Tizanidine Interaction
Drug interaction information between Fluvoxamine and Tizanidine.
Fluvoxamine and Tizanidine have a documented major interaction in FDA labeling.
FDA drug labeling documents a major-severity interaction between Fluvoxamine and Tizanidine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Fluvoxamine blocks the enzyme that normally clears tizanidine from your body. This leads to much higher amounts of tizanidine in your blood than intended.
FDA Label Information
( 7.2 , 12.3 ) 7.1 Strong CYP1A2 Inhibitors Concomitant use of tizanidine with strong cytochrome P450 1A2 (CYP1A2) inhibitors (e.g., fluvoxamine, ciprofloxacin) is contraindicated.
Fluvoxamine Also Interacts With
- Lithium moderate
- Phenelzine moderate
- Tasimelteon moderate
- Metoprolol minor
- Omeprazole minor
Tizanidine Also Interacts With
- Ciprofloxacin major
- Famotidine moderate
- Acyclovir minor
- Verapamil minor
- Amiodarone minor
Frequently Asked Questions
What SPL severity band is on file for Fluvoxamine + Tizanidine?
Compiled FDA labeling labels this pair major. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Fluvoxamine has 40 labeled pairs on file vs Tizanidine's 17. In the major band specifically: Fluvoxamine has 1; Tizanidine has 2 (also Ciprofloxacin).
What mechanism field is on file for Fluvoxamine and Tizanidine?
Fluvoxamine blocks the enzyme that normally clears tizanidine from your body. This leads to much higher amounts of tizanidine in your blood than intended.
Tizanidine carries more major-labeled pairs than Fluvoxamine
SPL source-record counts only. This page's band is major · classes on file: Fluvoxamine (Selective Serotonin Reuptake Inhibitor (SSRI)); Tizanidine (Central Alpha-2 Agonist (Muscle Relaxant)).
Tizanidine has 2 major-labeled pairs vs Fluvoxamine's 1.
1 major · 3 moderate · 36 minor · 40 total
Fluvoxamine has no other major-band peer in this dataset besides Tizanidine.
2 major · 1 moderate · 14 minor · 17 total
- Other major peers for Tizanidine
- Ciprofloxacin
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.