A study was undertaken to develop a method that could be used an an indication of the absorption of steroids. It was demonstrated that 17-hydroxycorticosteroids in urine could be quantitatively determined via absorptivity values obtained through the use of standard hydrocortisone-alcohol solutions or standard solutions of hydrocortisone in urine utilizing the blue tetrazolium assay method. This method is dependent upon the hydrolysis of conjugated urinary steroids by beef liver glucuronidase. The resultant concentration of 17-hydroxycorticosteroids is determined colorimetrically using blue tetrazolium.