Lithium-Induced Hypercalcemia
In a poster at the 5th Biennial Conference of the International Society for Bipolar Disorders, researchers from the Netherlands including E.J. Regeer described the prevalence of hypercalcemia (high calcium levels) in patients with bipolar disorder who are treated with lithium. In a study of 314 patients taking lithium, Regeer and colleagues found that calcium levels were elevated in 15.6% of the patients, and the length of time patients had been treated with lithium was significantly related to the degree of hypercalcemia. It is recommended that blood levels of calcium be monitored in patients on lithium.
The researchers recommended testing for parathyroid hormone in blood in order to exclude other causes of hypercalcemia. They also suggested that when lithium cannot safely be discontinued or when its discontinuation does not resolve the hypercalcemia, other treatment for high blood calcium, including removal of the parathyroid, may be necessary.