Theophylline and Levofloxacin Interaction
Drug interaction information between Theophylline and Levofloxacin.
Theophylline and Levofloxacin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Theophylline and Levofloxacin. 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
Levofloxacin can prevent your body from breaking down theophylline as quickly as usual. This can cause theophylline to build up to unsafe levels in your blood.
FDA Label Information
7.5 Theophylline No significant effect of levofloxacin on the plasma concentrations, AUC, and other disposition parameters for theophylline was detected in a clinical study involving healthy volunteers. Similarly, no apparent effect of theophylline on levofloxacin absorption and disposition was observed. However, concomitant administration of other fluoroquinolones with theophylline has resulted in prolonged elimination half-life, elevated serum theophylline levels, and a subsequent increase in the risk of theophylline-related adverse reactions in the patient population.
Theophylline Also Interacts With
- Metoprolol major
- Albuterol major
- Omeprazole major
- Amoxicillin major
- Famotidine major
Levofloxacin Also Interacts With
- Probenecid major
- Cimetidine major
- Warfarin minor
- Cyclosporine minor
- Digoxin minor
Frequently Asked Questions
What SPL severity band is on file for Theophylline + Levofloxacin?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Theophylline has 86 labeled pairs on file vs Levofloxacin's 8. In the moderate band specifically: Theophylline has 5 (also Bupropion, Clarithromycin, Febuxostat, Rifampin); Levofloxacin has 1.
What mechanism field is on file for Theophylline and Levofloxacin?
Levofloxacin can prevent your body from breaking down theophylline as quickly as usual. This can cause theophylline to build up to unsafe levels in your blood.
Theophylline carries more major-labeled pairs than Levofloxacin
SPL source-record counts only. This page's band is moderate · classes on file: Theophylline (Methylxanthine Bronchodilator); Levofloxacin (Fluoroquinolone Antibiotic).
Theophylline has 27 major-labeled pairs vs Levofloxacin's 2. This page itself is in the moderate band, not the major band.
27 major · 5 moderate · 54 minor · 86 total
- Other moderate peers for Theophylline
- Bupropion
- Clarithromycin
- Febuxostat
- Rifampin
2 major · 1 moderate · 5 minor · 8 total
Levofloxacin has no other moderate-band peer in this dataset besides Theophylline.
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.