-Causes of Hyponatremia-

Decreased sodium levels in plasma is known as hyponatremia. It is often caused by loss through the gastrointestinal tract via vomiting or diarrhea. Sodium is excreted through sweat and urine, so use of diuretics or excessive sweating can also lead to hyponatremia.

Sodium retention is regulated by aldosterone, a hormone produced by the adrenal glands. As such, adrenal insufficiency (also known as Addison’s disease) leads to hyponatremia via decreased sodium reabsorption in the kidneys.

Antidiuretic Hormone (ADH) increases water retention in the kidneys. When too much ADH is produced, such as with Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH), this excess water decreases the amount of sodium in the plasma through a dilutional effect.

Excessive water intake or conditions causing fluid retention can also lead to hyponatremia for the same reason. Some of these conditions include heart failure, cirrhosis, renal failure, or nephrotic syndrome.

-Symptoms of Hyponatremia-

Low levels of sodium in plasma leads to fluid moving into tissues in an attempt to maintain osmolality. This is also known as edema. Swelling in the brain leads to symptoms such as headaches, confusion, dizziness, seizures, and even coma or death in severe cases.

-Causes of Hypernatremia-

Increased sodium levels in plasma is known as hypernatremia. It is commonly caused by dehydration. Excessive sodium intake or the use of certain diuretics are some other causes. Diabetes Insipidus is caused by decreased production of Antidiuretic Hormone (ADH) or improper response by the kidneys to this hormone. This leads to frequent urination and hypernatremia as fluid is lost.

-Symptoms of Hypernatremia-

The most common symptom of hypernatremia is thirst as the body seeks water to restore the osmotic balance. Vomiting and diarrhea may also occur for the same reason. Neurological symptoms may also occur as fluid moves out of brain cells such as confusion, seizures, or coma in severe cases.