Two novel methods are presented for the spectrophotometric determination of colchicoside (COLSID) Method A involves the reaction of COLSID with Fe(III) to form complex and method B is based on the reaction of the drug with NH(2)OH HCl, the absorbances of which are measured at 458 nm and 395 nm respectively The calibration graphs are found to be linear over 20 00-120 00 and 20 00-100 00 mu gmL(-1) for methods A and B respectively The apparent molar absorptivity for COLSID-Fe(III) and COLSID-NH(2)OH HCl are 0 146 x10(4) and 1 449x10(4) Lmol(-1) cm(-1) respectively The methods are successfully applied to the assay of COLSID in pharmaceutical preparations