What would happen if the parathyroid glands were removed?

Low blood calcium: Removal of the parathyroid glands would immediately result in a low blood calcium and ususally tingling, muscle cramps, impaired thinking and occasionally, seizures. It can be treated with a powerful form of vitamin d and calcium.

It depends.: Most people have four parathyroids, and even one parathyroid can produce enough parathyroid hormone to keep the calcium level fine. If, however, all the parathyroid glands are removed, then a serious life-threatening low calcium level can occur, causing tetany, similar to the tetanus that tetanus shots are supposed to prevent. This requires large amounts of lifelong calcium pills and vitamin d.