Tetany

Spasms and twitching of the muscles, most commonly in the hands and feet, although the muscles of the face, larynx, or spine may also be affected. The spasms are caused by a biochemical disturbance and are painless at first; if the condition persists, the spasms tend to become increasingly painful. Muscle damage may result if the underlying cause is not treated. The most common underlying cause is hypocalcaemia. Other causes include hypokalaemia, hyperventilation during a panic attack, or, more rarely, hypoparathyroidism.