Primary hyperparathyroidism (PHPT) is a common endocrinological process, characterized by chronic elevation of serum concentrations of calcium and parathyroid hormone (PTH). Many years ago, the most frequent forms of clinical presentation were symptomatic renal or skeletal disease with moderate or severe hypercalcemia; however, currently, most patients have few symptoms and mild hypercalcemia. A new form of presentation called normocalcemic PHPT has also been described but clinical consequences are not well established. The biochemical profile of PHPT is characterized by hypercalcemia and high or inappropriately normal PTH concentrations. Parathyroidectomy is the only definitive cure. Medical treatment with the calcimimetic cinacalcet has been shown to normalize calcemia in a high percentage of cases.