Diflunisal and Lithium Interaction
Drug interaction information between Diflunisal and Lithium.
Diflunisal and Lithium have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Diflunisal and Lithium. 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
Diflunisal makes it harder for the kidneys to clear lithium from the body. This leads to higher levels of lithium in your blood.
FDA Label Information
Lithium NSAIDs have produced an elevation of plasma lithium levels and a reduction in renal lithium clearance. The mean minimum lithium concentration increased 15% and the renal clearance was decreased by approximately 20%. Thus, when NSAIDs and lithium are administered concurrently, subjects should be observed carefully for signs of lithium toxicity.
Diflunisal Also Interacts With
- Methotrexate moderate
- Cyclosporine moderate
- Celecoxib moderate
- Indomethacin moderate
- Mefenamic Acid moderate
Lithium Also Interacts With
- Amlodipine/Benazepril major
- Risperidone major
- Amiloride moderate
- Amiodarone moderate
- Amlodipine/Valsartan moderate
Frequently Asked Questions
What SPL severity band is on file for Diflunisal + Lithium?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Lithium has 90 labeled pairs on file vs Diflunisal's 17. In the minor band specifically: Diflunisal has 6 (also Hydrochlorothiazide, Furosemide, Aspirin, Acetaminophen); Lithium has 65 (also Aripiprazole, Asenapine, Canagliflozin, Candesartan).
What mechanism field is on file for Diflunisal and Lithium?
Diflunisal makes it harder for the kidneys to clear lithium from the body. This leads to higher levels of lithium in your blood.
Lithium carries more major-labeled pairs than Diflunisal
SPL source-record counts only. This page's band is minor · classes on file: Diflunisal (Nonsteroidal Anti-Inflammatory Drug (NSAID)); Lithium (Mood Stabilizer).
Lithium has 2 major-labeled pairs vs Diflunisal's 0. This page itself is in the minor band, not the major band.
0 major · 11 moderate · 6 minor · 17 total
- Other minor peers for Diflunisal
- Hydrochlorothiazide
- Furosemide
- Aspirin
- Acetaminophen
2 major · 23 moderate · 65 minor · 90 total
- Other minor peers for Lithium
- Aripiprazole
- Asenapine
- Canagliflozin
- Candesartan
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.