Hypercalcaemia in thyrotoxicosis with and without hyperparathyroidism.

Two cases of thyrotoxicosis with hypercalcaemia are reported. The hypercalcaemia in one of the patients was a manifestation of hyperthyroidism and in the other was due to co-existent hyperparathyroidism. The literature is reviewed and the effect of thyroid hormone on calcium metabolism is discussed. Routine plasma calcium estimations should be performed in all cases of thyrotoxicosis.