How does 1) cortisol insufficiency and 2) hypothyroidism cause hyponatremia ?
Hello Tanaya Shah,
Cortisol deficiency results in increased hypothalamic secretion of CRH. CRH plays the role of an additional ADH secretagogue. ADH induced water retention results in hyponatremia.
Hypothyroidism reduces cardiac output. As a result, there is increased ADH secretion causing hyponatremia. This is only seen in chronic hypothyroidism. Thank you.