Hyponatremia causes

Hyponatremia caused by omeprazole has been reported in a 78-year-old woman who was taking omeprazole 20 mg/day for esophagitis, in a 74-year-old man (7), and in an elderly alcoholic (SEDA-17, 419). 

Bechade D, Algayres IP, Henrionnet A, Texier F, Bili H, Coutant G, Helie C, Daly IP. Hyponatremie secondaire a la prise d omeprazole. [Secondary hyponatremia caused by omeprazole treatment.] Gastroenterol Clin Biol 2000 24(6-7) 684-5. 

Depletional hyponatremia (excess loss of Na ) is almost always accompanied by a loss of ECF water, but to a lesser extent tlian the Na loss. Hypovolemia is apparent in the physical examination (orthostatic hypotension, tachycardia, decreased skin turgor). Loss of isosmotic or hypertonic fluid is the cause and this can occur through renal or extrarenal losses. If urine Na is low (generally <10 mmol/L), the loss is extrarenal (see Figure 46-2) because the kidneys are properly retaining filtered Na in response to increased aldosterone (stimulated by the hypovolemia and hyponatremia). Causes of extrarenal loss of Na" in excess of H2O include losses from the gastrointestinal tract or skin (see Figure 46-2). 

Patients with hypotonic hyponatremia caused by volume depletion should initially receive normal saline followed by 0.45% saline once signs of extracellular fluid volume depletion abate in order to avoid overly rapid correction of the serum sodium concentration. 

ECF volume deficit (ECFVd) is dependent on the patient s weight, age, and the degree of volume depletion, and is difficult to precisely estimate. An ECFVd loss that is equal to a 10% to 15% decrease in body weight is associated with the development of postural hypotension. An ECFVd loss as low as 5%, however, can result in hyponatremia caused by nonosmotic ADH release as a result of stimulation of baroreceptors located in the chest and neck. The ECFVd of patients can be estimated as illustrated in this case a 42-year-old male weighs 70 kg on initial examination and presents with postural hypotension and has a serum sodium of 125 mEq/L ... 

Verbalis JG, Gullans SR. Hyponatremia causes large sustained reductions in brain content of multiple organic osmolytes in rats. Brain Res 1991 567 274-282. 

Endocrine Severe hyponatremia caused by the syndrome of inappropriate ADH secretion secondary to olanzapine has been reported [107" ] three other cases were reported to a Dutch pharmacovigilance center in 2006. 

Watch patients taking lithium for signs of toxicity when hyponatremia is present. This toxicity can occur even if the lithium dosage has been consistent because hyponatremia causes an increase in lithium retenhon. 

In long-term treatment, the thia2ides may produce hypokalemia, hyperglycemia, hypemricemia, and a 5% increase in plasma cholesterol indapamide has been shown not to increase plasma cholesterol or Hpids at therapeutic doses (21—23). The decrease of plasma potassium, ie, hypokalemic effect, is dose-dependent, and can be avoided if high doses are avoided (24,25). Thia2ides can cause hyponatremia in patients with large water intake while on the dmg (26,27) hyponatremia may be associated with nausea, vomiting, and headaches. 

Sodium is administered for hyponatremia (low blood sodium). Examples of causes of hyponatremia are excessive diaphoresis, severe vomiting or diarrhea, excessive diuresis, and draining intestinal fistulas. 

Higher vasopressin concentrations are linked to dilutional hyponatremia and a poor prognosis in HF. Vasopressin exerts its effects through vasopressin type la (Vla) and vasopressin type 2 (V2) receptors.5,7 Vasopressin type la stimulation leads to vasoconstriction, while actions on the V2 receptor cause free water retention through aquaporin channels in the collecting duct. Vasopressin increases preload, afterload, and myocardial oxygen demand in the failing heart. 

Normal saline is an isotonic fluid composed of water, sodium, and chloride. It provides primarily ECF replacement and can be used for virtually any cause of TBW depletion. Common uses of normal saline include perioperative fluid administration volume resuscitation of shock, hemorrhage, or burn patients fluid challenges in hypotensive or oliguric patients and hyponatremia. 

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. 

Hypotonic hyponatremia with an increase in ECF is also known as dilutional hyponatremia. In this scenario, patients have an excess of total body sodium and TBW however, the excess in TBW is greater than the excess in total body sodium. Common causes include CHF, hepatic cirrhosis, and nephrotic syndrome. Treatment includes sodium and fluid restriction in conjunction with treatment of the underlying disorder—for example, salt and water restrictions are used in the setting of CHF along with loop diuretics, angiotensin-converting enzyme inhibitors, and spironolactone.15... 

In hypotonic hyponatremia with a decreased ECF volume, patients usually have a deficit of both total body sodium and TBW, but the sodium deficit exceeds the TBW deficit. Common causes include diuretic use, profuse sweating,... 

Isolated seizures that are not epilepsy can be caused by stroke, central nervous system trauma, central nervous system infections, metabolic disturbances (e.g., hyponatremia and hypoglycemia), and hypoxia. If these underlying causes of seizures are not corrected, they may lead to the development of recurrent seizures I or epilepsy. Medications can also cause seizures. Some drugs that are commonly associated with seizures include tramadol, bupropion, theophylline, some antidepressants, some antipsy-chotics, amphetamines, cocaine, imipenem, lithium, excessive doses of penicillins or cephalosporins, and sympathomimetics or stimulants. 

Additionally, the risk of a subsequent seizure must be determined. If there is an underlying treatable cause, such as hyponatremia or a CNS infection, the risks of another seizure and the development of epilepsy are very small. In these cases, the only pharmacotherapy that is necessary is to correct the underlying problem and possibly short-term use of an AED. Risk factors for repeated seizures in patients without an underlying disorder include ... 

Hyponatremia, hypernatremia, hyperkalemia, hypocalcemia, hypomagnesemia, and hypoglycemia can cause SE... 

Topiramate Topamax Suspension 300 mg/5 mL Tablet 25, 100, 200 mg Doses should be slowly adjusted up and down according to response and adverse effects (e.g., 150-300 mg twice daily and increase by 300-600 mg/day at weekly intervals) 50-200 mg/day in divided doses drug-drug interactions than carbamazepine, but causes more gastrointestinal side effects and hyponatremia Evidence is limited regarding efficacy Not recommended for the... 

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. 

Adverse Effects Adverse effects due to oxcarbazepine include drowsiness, dizziness, gastrointestinal upset, and hyponatremia, the latter two of which may be more likely than with carbamazepine. It is less likely than carbamazepine to cause hematologic abnormalities.34... 

Caucasians (Okpaku et al, 2005 Strickland etal, 1995). Presumably this difference is a result of the tendency of African Americans to retain sodium. Sodium retention offered a selective survival advantage for slaves bought to America over the middle passage since hyponatremia was believed the major cause of mortality (Hildreth 8c Saunders, 1991). 

If uncontrolled, hyponatremia may cause increased intracranial pressure, brain herniation and death 595... 

The neuromuscular junction and muscle are more resistant to changes in sodium concentration, to which they are minimally permeable at rest. In fact, the consequences of sodium disturbance relate instead to the role of this ion in maintaining the osmotic equilibrium between the brain and plasma and range from depression of consciousness, coma and seizures caused by hyponatremia, to brain shrinkage and tearing of superficial blood vessels due to excessive serum osmolarity due to hypernatremia. 

Dose-related side effects include dizziness, sedation, headache, ataxia, fatigue, vertigo, abnormal vision, diplopia, nausea, vomiting, and abdominal pain. It causes more hyponatremia than carbamazepine. 

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