This article waslast modified on 10 July 2017.
A condition characterised by underactivity of the parathyroid glands and reduced production of parathyroid hormone (PTH), a hormone that controls calcium and phosphate levels in blood and calcium in bone. Symptoms may include tingling in the fingers and toes, muscle aches and spasms, fatigue, dry skin and brittle nails, headaches, anxiety, and depression.