Chemistry and pharmacology of naproxen.

The need for a nonsteroidal anti-inflammatory agent effective in rheumatoid arthritis, osteoarthritis, gout, ankylosing spondylitis and related diseases with reduced side effects when compared to existing drugs led us to develop naproxen: d-2-(6'-methoxy-2'-naphthyl)-propionic acid. This new agent is a highly effective anti-inflammatory, analgetic, and antipyretic agent in the rodent administered orally. In a rat paw edema test for anti-inflammatory activity naproxen was 55 times more active than aspirin. Analgetic activity was assessed by three different assay procedures. In the mouse phenylquinone writhing test naproxen was 7 times as effective as aspirin. In the rat yeast-induced paw edema and the rat carrageenin paw edema analgetic assays the test compound was 10 and 20 times more effective than aspirin, respectively. A yeast-induced pyresis model in the rat indicated that naproxen was 22 times more potent than the standard aspirin. The relative potency of naproxen to phenylbutazone and indometacin is presented.