There are many different causes of parathyroid hypothyroidism. Severe hypomagnesaemia, hypophosphataemia, and the use of certain medications can lead to a reversible deficiency in PTH production or secretion, resulting in transient hypoparathyroidism, which usually recovers when these causes are removed. However, in most cases, the cause of parathyroidism is destruction of the parathyroid glands, congenital or hereditary abnormalities in parathyroid development. These causes of parathyroidism are usually incurable and require lifelong treatment with calcium and active vitamin D. The aim is to correct hypocalcaemia, bring serum calcium levels to or near normal, reduce symptoms and eliminate twitchy episodes, prevent or reduce long-term parathyroidism chronic complications, and to avoid vitamin D toxicity.