Hyponatremia with treatment

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 patients with myocardial infarction, in whom phenoxybenzamine has been used to improve circulation, it can cause or aggravate pulmonary edema this could be explained by severe hyponatremia during treatment with phenoxybenzamine (SEDA-13,113). 

A 78-year-old woman developed severe symptomatic hyponatremia after treatment with anhydrous theophylline and 6 months later developed hyponatremia after treatment with co-trimoxazole for a presumptive urinary tract infection (74). 

Elisaf M, Theodorou J, Pappas C, Siamopoulos K. Successful treatment of hyponatremia with angiotensin-converting enzyme inhibitors in patients with congestive heart failure. Cardiology 1995 86 477 80. 

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. 

Hypertonic hyponatremia is usually associated with significant hyperglycemia. Glucose is an osmotically active agent that leads to an increase in TBW with little change in total body sodium. For every 60 mg/dL (3.33 mmol/L) increase in serum glucose above 200 mg/dL (11.1 mmol/L), the sodium is expected to decrease by approximately 1 mEq/L (1 mmol/L). Appropriate treatment of the hyperglycemia will return the serum sodium to normal.15... 

Carbamazepine Manufacturer recommends CBC and platelets (and possibly reticulocyte counts and serum iron) at baseline, and that subsequent monitoring be individualized by the clinician (e.g., CBC, platelet counts, and liver function tests every 2 weeks during the first 2 months of treatment, then every 3 months if normal). Monitor more closely if patient exhibits hematologic or hepatic abnormalities or if the patient is receiving a myelotoxic drug discontinue if platelets are less than 100,000/mm3, if white blood cell (WBC) count is less than 3,000/mm3 or if there is evidence of bone marrow suppression or liver dysfunction. Serum electrolyte levels should be monitored in the elderly or those at risk for hyponatremia. Carbamazepine interferes with some pregnancy tests. 

Treatment of hyponatremia is associated with a risk of osmotic demyelina-tion syndrome, a severe neurologic complication that can develop if the rate of serum sodium correction exceeds 8 to 12 mEq/L within 24 hours. 

The activity of the renin-angiotensin system is reduced with age (Muhlberg and Platt 1999). The ability of the kidney to concentrate urine maximally after water deprivation decreases with age, as does the ability to excrete a water and salt load, particularly during the night. Nocturnal polyuria is common in the elderly (Lubran 1995). Diuretics are commonly used in the elderly. There is an increased risk for hypokalemia and hyponatremia from diuretics in the elderly (Passare et al. 2004). Electrolyte disturbances may also be caused by several types of drugs in the elderly and it is important to monitor serum electrolyte levels in the elderly. Treatment with... 

Hyponatremia/Hypochloremia - A chloride deficit is generally mild and usually does not require specific treatment, except in extraordinary circumstances (as in liver or renal disease). Thiazide-induced hyponatremia has been associated with death and neurologic damage in elderly patients. 

Hyponatremia Clinically significant hyponatremia generally occurred during the first 3 months of treatment with oxcarbazepine, although there were patients who first developed a serum sodium less than 125 mmol/L greater than 1 year after initiation of therapy. Most patients who developed hyponatremia were asymptomatic, but patients in the clinical trials were frequently monitored and some had their oxcarbazepine dose reduced or discontinued or had their fluid intake restricted for hyponatremia. When oxcarbazepine was discontinued, normalization of serum sodium generally occurred within a few days without additional treatment. 

A toxicity that is unique to cyclophosphamide and ifosfamide is cystitis. Dysuria and decreased urinary frequency are the most common symptoms. Rarely, fibrosis and a permanently decreased bladder capacity may ensue. The risk of development of carcinoma of the bladder also is increased. Large intravenous doses have resulted in impairment of renal water excretion, hyponatremia, and increased urine osmolarity and have been associated with hemorrhagic subendocardial necrosis, arrhythmias, and congestive heart failure. Interstitial pulmonary fibrosis may also result from chronic treatment. Other effects of chronic drug treatment include infertility, amenorrhea, and possible mutagenesis and carcinogenesis. 

ADH antagonists, including nonpeptide analogues that may be taken orally, have been developed with specificity for each of the receptor types. In the future, those that block Vj receptors may be useful in treating hypertension, and those that block Vj receptors may be useful in any condition of excessive water retention or hyponatremia, for which so far there is no satisfactory therapeutic treatment. 

The syndrome of inappropriate antidiuretic hormone secretion, with resultant hyponatremia, may be induced by carbamazepine treatment. Alcoholic patients may be at greater risk for hyponatremia. 

Antidiuretic hormone is also elevated in response to diminished effective circulating blood volume, as often occurs in congestive heart failure. When treatment by volume replacement is not desirable, hyponatremia may result. As for SIADH, water restriction is often the treatment of choice. In patients with congestive heart failure, this approach is often unsuccessful in view of increased thirst and the large number of oral medications being used. In these patients, conivaptan may be particularly useful because it has been found that... 

Shindel A, Tobin G, Klutke C. Hyponatremia associated with desmopressin for the treatment of nocturnal polyuria. Urology 2002 60(2) 344. 

Brodzikowska-Pytel A, Giembicki J. Hyponatremia as a complication of nocturnal enuresis treatment with desmopressin in a child. Pediatr Pol 1999 74 79-83. 

Asian patients have been proposed to be at higher risk of SIADH during treatment with vincristine. Between 1983 and 1999, 76 cases of hyponatremia and/or SIADH related to the use of vincristine were reported to the global adverse event database of Eli Lilly and Company. The average age of the patients was 36 years (range 2 weeks to 86 years) and 62% were male. Most of the patients had received vincristine for leukemia or lymphomas. Of the 76 reports, 39 included background information on race 35 patients were Asian, three were Caucasian, and one was black. The authors concluded that there may be a correlation between race and vinca alkaloid-associated SIADH/hyponatremia however, the reasons are still unclear (1198). 

On the basis of these studies, conivaptan HCl (1) has been approved by the FDA for the treatment of hospitalized patients with euvolemic and hypervolemic hyponatremia but is not currently indicated for the treatment of congestive heart failure.28 Due to its aquaretic effects, conivaptan use is contraindicated in patients with hypovolemic... 

SSRIs can reportedly cause hyponatremia (SEDA-18, 20 SEDA-26,13). In a case-control study of hyponatremia in 39 071 psychiatric inpatients and outpatients, the incidence of antidepressant-induced hyponatremia was 2.1% (33). SSRI users had a three times higher risk of developing hyponatremia relative to users of other antidepressant drugs (OR = 3.1 95% Cl = 1.3, 8.6). Additional risk factors included older age and concomitant treatment with diuretics. 

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