A total of 100 cases hyperthyroid patients were selected for this prospective study. The hyperthyoidism was confirmed by thyroid function tests and scintigraphy. Of these100 patients 60 (60%) patients had elevated serum alkaline phosphatase(ALP)and decreased bone mineral density (BMD) and 20(20%) patients had normal ALP and normal BMD. All 100 patients underwent total thyroidectomy. 20 patients with normal ALP did not show a shift in calcium levels and 80 patients with elevated ALP showed shift in calcium levels (1 to 1.5 gm%) 40 (40%) patients with their calcium levels less than 9.5gm% and elevated ALP developed carpopedal spasm in postoperative period. Hence we conclude that the combination of low normal calcium (< 9.5%) and elevated ALP has a high predictive value for postoperative carpopedal spasm .