Pharmacological properties of the anti-inflammatory agent pyridyl-biphenylyl-acetamide (diphenpyramide)

Pyridyl-biphenylyl-acetamide (diphenpyramide, Z-876) is a new bisphenylalcanoic derivative with marked anti-inflammatory, analgesic, antipyretic and uricosuric properties. It is more active than phenylbutazone in the Adjuvant polyarthritis in the rat when given prophylactically or therapeutically. It is thrice as active as phenylbutazone and ten times as active as acetylsalicylic acid (ASA) on the carrageenin-induced edema of the hind-paw. Diphenpyramide is characterized by low acute toxicity and by weak ulcerogenic activity. On the carrageenin-induced edema the therapeutic index of diphenpyramide is 30 times higher than that of indometacin and the ratio between the ED50 and the UD50 (ulcerogenic dose in 50% of the treated rats) is 39 times higher than that of ASA.