Version July 2025
FHH: familial hypocalciuric hypercalcemia; PTH: parathyroid hormone; PTHrP: parathyroid hormone-related peptide; SPEP: serum protein electrophoresis; UPEP: urine protein electrophoresis.
* Some medications associated with hypercalcemia include thiazide diuretics, lithium, teriparatide, abaloparatide, excessive vitamin A, and excessive theophylline. If possible, any medication or supplement that may be causing hypercalcemia should be discontinued.
¶ Some clinicians obtain a PTH level at this step, when verifying the initial elevated calcium level.
Δ Serum PTH typically ranging from 35 to 65 pg/mL in an assay whose normal range is 10 to 60 pg/mL.
◊ Refer to UpToDate content on primary hyperparathyroidism.
§ Refer to UpToDate content on primary hyperparathyroidism and FHH for details.
¥ Additional work-up is warranted to identify malignancy.
‡ Serum 25-hydroxyvitamin D must be markedly elevated before hypercalcemia develops. Although the serum concentration of 25-hydroxyvitamin D at which hypercalcemia typically occurs is undefined, many experts define vitamin D intoxication as a value >150 ng/mL (374 nmol/L).
