EFFECT OF LITHIUM ON SERUM-CALCIUM LEVEL AND PARATHYROID FUNCTION IN MANIC-DEPRESSIVE PATIENTS

The purpose of this study is to find out whether hypercalcemia and hyp erparathyroidism are rare or not in manic-depressive patients taking l ithium carbonate. The subjects were 13 patients receiving lithium and 19 healthy subjects not receiving it as normal controls. Serum ionized calcium (Ca++), serum parathyroid hormone (PTH), urinary calcium and cyclic AMP (cAMP) were measured. Cervical ultrasonographic examination was also performed. The mean serum Ca++ level in the lithium administ ered group was significantly higher than that in the control group (P< 0.02). There was no significant difference between the serum PTH level s in the two groups. The mean urinary calcium level in the lithium adm inistered group was below the normal range, but the mean urinary cAMP level was within the normal range. Although a parathyroid cyst was fou nd in one lithium administered patient on ultrasonographic examination , no swelling of the parathyroid gland was observed in the other patie nts in the lithium administered group or in any of the control subject s. In the present study, no distinct hyperparathyroidism was found in the patients in the lithium administered group. Lithium administration affects calcium metabolism in manic-depressive patients and hypercalc emia seems to be one of the complications needing attention at the tim e of lithium administration.