cause of hyponatremia

Major causes of hyponatremia

Disorders in which ADH levels are elevated
• Effective circulating volume depletion
• True volume depletion—vomiting, diarrhea, bleeding, urinary loss
• Congestive heart failure and cirrhosis
• Thiazide diuretics
• Syndrome of inappropriate ADH secretion
• Hormonal changes: adrenal insufficiency, hypothyroidism, and pregnancy

Disorders in which ADH may be appropriately suppressed
• Advanced renal failure
• Primary polydipsia
• Beer drinkers’ potomania

Pseudohyponatremia
• High plasma osmolality: hyperglycemia or mannitol
• Normal plasma osmolality: hyperlipidemia, glycine solutions, and hyperproteinemia