The parathyroids are four small glands that are situated behind the thyroid. There role is to regulate the amount of calcium in the blood and it is an important element for functioning of muscles and is also very important to maintain strength of bones. Occasionally the gland can produce too much parathyroid hormone leading to a raised level of calcium in the blood. This is often discovered on incidental blood tests. A raised level of calcium can cause problems such as osteoporosis (weak bones), kidney and bladder stones, muscle aches and pains and tummy aches and pains and also mood change. The commonest cause for an over active parathyroid gland is a benign (non cancerous) tumour of the parathyroid gland called parathyroid adenoma. If the calcium is quite high or there are symptoms these are best treated and the treatment is surgical removal. Often the gland is localised using special scans. The operation to remove the parathyroid gland is virtually the same procedure as for a thyroid gland, through the same incision and normally the calcium will return to normal very quickly.