condition characterized by rhythmic cramping of the muscles of the hands and feet, muscle twitching, and possible spasms of the larynx, with difficulty breathing, nausea, vomiting, convulsions (convulsion), and pain. Tetany results from a metabolic imbalance; it may be caused by too little calcium, potassium, or magnesium in the circulation or by an over-acid or over-alkaline condition of the body. It may accompany poorly controlled hypoparathyroidism, hypophosphatemia, osteomalacia, renal disorders (renal system disease), or malabsorption syndromes. Treatment is directed at restoring metabolic balance, as by intravenous administration of calcium in cases of hypocalcemia (calcium deficiency).