Naproxen poisoning

Pathophysiology

• Exact mode of action unknown, not mediated through the pituitary axis.
• Along with most other NSAIDs, produces gastrointestinal damage.
• Lesions vary from erythema, hemorrhage and erosion to ulceration and peritonitis.
• Degree of gastrointestinal intolerance depends on the dose-level and the duration of drug administration.
• The dog has a relatively low tolerance for the drug.
• Gastrointestinal lesions have been seen following both parenteral and oral administration.

• Inhibits prostaglandin cyclo-oxygenase activity, which results in a prostaglandin deficiency at the tissue level.
• Ten times more potent than aspirin.
• Half-life of 74 hours.
• Naproxen may induce nephritis. Glomerular nephritis, interstitial nephritis and nephrotic syndrome have been reported in humans following use of naproxen.