Celecoxib × Lithium

NSAIDs (including selective COX-2 inhibitors like celecoxib) reduce renal lithium clearance. Lithium plasma levels rise.

Tremor, muscle twitching, nausea, vomiting, diarrhoea, poor coordination and confusion; severe cases progress to seizures and coma. Toxicity is expected at serum lithium concentrations of about 1.5 mmol/L and above, but some patients develop it at lower levels, including within the therapeutic range.

The UK National Institute for Health and Care Excellence (NICE) advises avoiding non-steroidal anti-inflammatory drugs (NSAIDs) in people on lithium if possible and warning them not to take over-the-counter NSAIDs (NICE CG185). If celecoxib is needed, prescribe it for regular use rather than as needed, and check lithium levels monthly until stable, then every 3 months (NICE CG185). When celecoxib is started or stopped, monitor the patient carefully (celecoxib SmPC), measure lithium more often, moving to weekly checks (lithium SmPC), and reduce the lithium dose according to levels and clinical response if needed (lithium SmPC; US lithium label, FDA). Take the lithium sample 12 hours after the last dose (lithium SmPC). Warn the patient about signs of lithium toxicity: diarrhoea, vomiting, coarse tremor, poor coordination, confusion and seizures (NICE NG222).