Lithium and Naproxen Concomitant Use
Concomitant use of lithium with naproxen is not listed as an absolute contraindication in major patient-facing references. [1][2]
Naproxen can increase lithium exposure by reducing renal lithium clearance. [1][2][3]
Interaction Severity and Expected Clinical Effect
NSAIDs are associated with elevated plasma lithium levels and reduced renal lithium clearance. [3]
This interaction is attributed to renal effects related to prostaglandin inhibition. [3]
Contraindication Status
The combination is described as a medicine interaction that requires avoidance or close monitoring in sources addressing lithium safety with other medicines. [1][2][4]
An absolute “contraindicated” designation is not stated in these references. [1][2]
Practical Risk Management
Lithium levels should be monitored more frequently when NSAIDs are used concomitantly. [4]
Close monitoring for lithium toxicity is advised because lithium toxicity risk increases with higher serum lithium levels. [2][3]
When Avoidance Is Most Important
Avoidance or enhanced monitoring is particularly important in settings that increase the likelihood of NSAID-related renal effects or reduced lithium clearance, including factors that predispose to dehydration or kidney dysfunction (renal lithium clearance reduction driven by NSAID renal prostaglandin inhibition). [3]
Expected Alternative Analgesic Strategies
If an NSAID is not essential, non-NSAID analgesic options are commonly used instead to reduce risk of lithium level elevation. [1][2]