Abstract Oral administration of two nonsteroidal anti-inflammatory drugs, ibuprofen and flurbiprofen, can suppress the Salmonella-induced arthritis in rats. The joint swelling index of arthritic paws showed suppression of arthritis in animals treated with the drugs, this effect being greater with flurbiprofen. Measurement of 5 eicosanoids in femoral vein plasma showed increase of arachidonic acid products in Salmonella-treated rats. Inhibition of joint inflammation resulting from treatment with ibuprofen and flurbiprofen is reflected by a decrease in concentration of all 5 eicosanoids which were found in the order: PGE 2 > TXB 2 > 6-keto-PGF 1α > PGE 1 > PGF 2α. These studies indicate that flurbiprofen is a more powerful anti-inflammatory agent than ibuprofen. However, since the joint disease was not completely cured, optimal intervention is quite likely to require modulation of the lipoxygenase pathway.