Hypokalaemic, hypophosphatemic thyrotoxic periodic paralysis.

Thyrotoxic periodic paralysis is an uncommon neuromuscular disorder frequently associated with severe hypokalemia. We describe a patient with hypophosphatemia occurring in the setting of hypokalemic thyrotoxic periodic paralysis, an association reported only once previously. A review of the literature indicates that this combined biochemical derangement may not be uncommon and that thyrotoxic periodic paralysis should be recognized as a potential cause of hypophosphatemia. The correction of both hypokalemia and hypophosphatemia may lead to a more rapid resolution of the associated acute neurologic syndrome.