The spectrofluorometric determination of piroxicam [4-hydroxy-2-methyl-N-(2-pyridyl)-2II-1,2-benzothiazine-3-carboxamide-1,1-dioxide] in pharmaceutical tablets is described. It involves excitation at 330 nm of an acid solution (HNO3 0.5 M) of the drug, and measurement of the fluorescence intensity at 440 nm. The linear range is 0.01-1.25 mu g ml(-1). (C) 1998 Elsevier Science B.V. All rights reserved.