dabigatran and naproxen

Pharmacodynamic interaction: Both dabigatran (a direct thrombin inhibitor) and naproxen (a non-steroidal anti-inflammatory drug) independently increase bleeding risk. Naproxen also damages the gastrointestinal mucosa and impairs platelet function, while dabigatran impairs thrombin-mediated clot formation. Additionally, NSAIDs can reduce renal perfusion, leading to decreased dabigatran clearance and elevated drug levels.

Co-administration significantly increases the risk of serious bleeding events, particularly gastrointestinal haemorrhage. The risk is further elevated in the elderly, in patients with a history of peptic ulcer or prior GI bleeding, and in those with renal impairment. Haematoma formation and bleeding at other sites may also occur.

Avoid concomitant use where possible. If anti-inflammatory therapy is needed, prefer an alternative such as paracetamol. When co-administration is unavoidable, use the lowest effective dose of naproxen for the shortest duration, consider gastroprotective therapy (e.g., a proton pump inhibitor), and monitor the patient closely for signs of bleeding, including haemoglobin levels and renal function. Dabigatran dose reduction may be required in renal impairment.

Well established through pharmacological principle, clinical trials, and post-marketing data. Major guidelines and prescribing information advise caution or avoidance of combined NSAID and anticoagulant therapy. No specific citations are provided here.