Hyponatremia causes/symptoms

Fluid balance and plasma electrolytes should be monitored to prevent this complication, particularly if repeated doses are required. Children seem to be particularly vulnerable to this complication (55). In a longterm, open study of 245 Swedish children given intranasal desmopressin 20-40 micrograms at night for enuresis, five had an asymptomatic fall in plasma sodium (36). Mild hyponatremia, which did not cause symptoms, was found in five of 399 children in an open, multicenter trial (56). 

Even low-dose intravenous cyclophosphamide can cause a syndrome that resembles inappropriate secretion of antidiuretic hormone, with severe hyponatremia and symptoms of water intoxication (SEDA-19, 347 SEDA-21, 386). A direct effect on the renal tubules is likely, but no other nephrotoxic effects have been documented. 

Hypernatremia (plasma Na >150 mmol/L) is always hyperosmolar, Symptoms of hypernatremia are primarily neurological (because of intraneuronal loss of H2O to the ECF) and include tremors, irritability, ataxia, confusion, and coma. As with hyponatremia, the rapidity of the development of hypernatremia wiU determine the plasma Na value at which symptoms occur. Acute development may cause symptoms when Na reaches 160 mmol/L, although in chronic hypernatremia, overt symptoms may not occur until Na exceeds 175 mmol/L. In chronic hypernatremia, the intracellular osmolality of CNS cells wiU increase to protect against intracellular dehydration. Because of this, rapid correction of hypernatremia can cause dangerous cerebral edema, as CNS cells will take up too much water if the ICF is hyperosmotic when normonatremia is achieved. ... 

Patients with weakened hearts, including the elderly, who often have decreased cardiac capacity to adapt to volume changes, or pediatric patients, who have smaller hearts with less capacity to handle large volumes, are at particular risk for cardiac overload. 2 Increased fluid volume also could cause a dilutional hyponatremia. Thus symptoms of low sodium concentration with fluid shifts including cerebral edema could occur. 4... 

Hypertonic saline is obviously hypertonic and provides a significant sodium load to the intravascular space. This solution is utilized very infrequently given the potential to cause significant shifts in the water balance between the ECF and the ICF. It is typically considered to treat patients with severe hyponatremia who have symptoms attributable to low serum sodium. 

Oxcarbazepine Hyponatremia (serum sodium concentrations less than 125 mEq/L) has been reported and occurs more frequently during the first 3 months of therapy serum sodium concentrations should be monitored in patients receiving drugs that lower serum sodium concentrations (e.g., diuretics or drugs that cause inappropriate antidiuretic hormone secretion) or in patients with symptoms of hyponatremia (e.g., confusion, headache, lethargy, and malaise). Hypersensitivity reactions have occurred in approximately 25-30% of patients with a history of carbamazepine hypersensitivity and requires immediate discontinuation. 

Hyponatremia Hyponatremia may be caused or aggravated by spironolactone, especially in combination with other diuretics. Symptoms include dry mouth, thirst, lethargy, drowsiness. 

The major limitation to the use of spironolactone is its liability to cause (sometimes lethal) hyperkalemia, particularly in the elderly, in patients with reduced renal function, and in patients who simultaneously take potassium supplements or ACE inhibitors. As with other diuretics, hyponatremia and dehydration can occur. Other less frequent adverse effects are gastrointestinal intolerance, neurological symptoms, and skin rashes. Hypersensitivity rashes and a lupus-Uke syndrome have been reported rarely. A few cases of mammary carcinoma have been reported and potential human metabolic products of spironolactone are carcinogenic in rodents. Second-generation effects have not been reported. 

A 24-year-old woman who was 24 weeks pregnant and had pregnancy-related hyponatremia and mood symptoms was given lithium and developed diabetes insipidus, which rapidly corrected her hyponatremia and caused central pontine and extrapontine myehnolysis [48 ]. 

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