hyponatremiaan

Hyponatremiaan is a term sometimes used to refer to hyponatremia, the condition in which the sodium concentration in the blood falls below 135 mEq/L. It reflects an excess of free water relative to sodium and can be acute or chronic. The most common form is hypotonic hyponatremia, which may be euvolemic, hypervolemic, or hypovolemic depending on fluid status. Causes include SIADH, congestive heart failure, liver cirrhosis, nephrotic syndrome, renal failure, and medications such as diuretics, selective serotonin reuptake inhibitors, tricyclic antidepressants, and antiepileptics. Low solute intake and certain endocrine disorders can also contribute.

Symptoms vary with severity and onset. Mild hyponatremia may be asymptomatic or cause malaise; moderate cases can present with confusion, dizziness, or nausea; severe hyponatremia can lead to seizures or coma. Rapid correction of chronic hyponatremia carries a risk of osmotic demyelination syndrome, so management aims for careful, controlled normalization.

Diagnosis starts with confirming low serum sodium and assessing plasma osmolality to distinguish hypotonic from isotonic or hypertonic hyponatremia. In hypotonic cases, urine osmolality and urine sodium help identify the cause, in the context of clinical volume status and evaluation for underlying disease. Additional tests may be guided by suspected etiologies such as adrenal or thyroid disorders.

Treatment depends on symptoms and duration. Severe, life‑threatening hyponatremia requires cautious administration of hypertonic saline (3% NaCl). In milder or chronic cases, fluid restriction and treatment of the underlying disorder are preferred. Options include salt supplementation, loop diuretics, or vasopressin receptor antagonists in select patients. Corrective speed is generally limited to about 6-8 mEq/L per 24 hours to minimize risk of osmotic demyelination, with desmopressin available if overcorrection is a concern.

Prognosis varies with cause and severity; hyponatremia is associated with increased morbidity and mortality, especially in hospitalized or critically ill individuals.