AQP2 and Hyponatremia: Amiodarone-induced hyponatremia is a rare complication, with only 17 cases described in the literature.26 The first case report was published in 1996.27 The mechanism by which amiodarone induces SIADH is still unclear.28 Iovino et al. suggested that amiodarone causes SIADH by stimulating anti-diuretic hormone secretion by the magnocellular neurons in the supraoptic and paraventricular nuclei of the hypothalamus or through the expression of water channel aquaporin-2 (AQP2) in the collecting ducts.29