Hyponatremia seizures with

In a retrospective analysis of all cases of hyponatremia associated with ecstasy (SEDA-25, 37) at the London Centre of the National Poisons Information Service from December 1993 to March 1996,17 patients were identified with a serum sodium concentration under 130 (range 107-128 mmol/1) (96). In 10, ecstasy was identified analytically, and six of them had SIADH. The clinical presentation was very consistent, with initial vomiting and delirium, and 11 had seizures. There was complete recovery in 14, but two died of cerebral edema 5 hours after ingestion. 

One report described adverse reactions in two pregnant women with von Willebrand disease (59). One went into premature labor after a single dose (attributed to the oxytocic effect of desmopressin) and the other had severe hyponatremia associated with seizures after repeated administration of desmopressin to cover a cesarean section. 

Hyponatremia is very common in hospitalized patients and is defined as a serum sodium concentration below 136 mEq/L (136 mmol/L). Clinical signs and symptoms appear at concentrations below 120 mEq/L (120 mmol/L) and typically consist of agitation, fatigue, headache, muscle cramps, and nausea. With profound hyponatremia (less than 110 mEq/L [110 mmol/L]), confusion, seizures, and coma maybe seen. Because therapy is also influenced by volume status, hyponatremia is further defined as (1) hypertonic hyponatremia (2) hypotonic hyponatremia with an increased ECF volume (3) hypotonic hyponatremia with a normal ECF volume and (4) hypotonic hyponatremia with a decreased ECF volume.16... 

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. 

Oxcarbazepine is less potent than carbamazepine, both in animal models of epilepsy and in epileptic patients clinical doses of oxcarbazepine may need to be 50% higher than those of carbamazepine to obtain equivalent seizure control. Some studies report fewer hypersensitivity reactions to oxcarbazepine, and cross-reactivity with carbamazepine does not always occur. Furthermore, the drug appears to induce hepatic enzymes to a lesser extent than carbamazepine, minimizing drug interactions. Although hyponatremia may occur more commonly with oxcarbazepine than with carbamazepine, most adverse effects that occur with oxcarbazepine are similar in character to reactions reported with carbamazepine. 

When oxytocin is used judiciously, serious toxicity is rare. The toxicity that does occur is due either to excessive stimulation of uterine contractions or to inadvertent activation of vasopressin receptors. Excessive stimulation of uterine contractions before delivery can cause fetal distress, placental abruption, or uterine rupture. These complications can be detected early by means of standard fetal monitoring equipment. High concentrations of oxytocin with activation of vasopressin receptors can cause excessive fluid retention, or water intoxication, leading to hyponatremia, heart failure, seizures, and death. Bolus injections of oxytocin can cause hypotension. To avoid hypotension, oxytocin is administered intravenously as dilute solutions at a controlled rate. 

A 3.5-year-old girl with mild hemophilia A received desmopressin 0.3 micrograms/kg intravenously 30 minutes before adenotonsillectomy. She drank 600 ml of fluid within the first 10 hours and then received 300 ml of intravenous 5% dextrose in 0.45% saline. She developed hyponatremia, headache, nausea, and seizures. 

A potential risk of desmopressin is of water intoxication with resultant hyponatremia (48), and rapid falls in serum sodium concentration can result in seizures. The risk is increased in infants and patients receiving hypotonic intravenous fluids, and such patients need to be carefully monitored. 

An 80-year-old woman with a high baseline fluid intake developed severe hyponatremia, with loss of consciousness and seizures, after a single dose of desmopressin 0.2 mg (49). 

A 47-year-old woman with von Willebrand disease, who was given desmopressin and intravenous fluids perioperatively, developed hyponatremia and seizures, which resolved after water restriction (50). 

There have been several reports of seizures in association with hyponatremia after intravenous administration of desmopressin to cover surgery in young children with congenital bleeding disorders such as mild hemophilia A or von Willebrand s disease (58-60). Hyponatremia and convulsions have occurred in children without congenital bleeding disorders who received desmopressin for urine concentration tests or to treat nocturnal enuresis (54,61,62). 

Odeh M, Oliven A. Coma and seizures due to severe hyponatremia and water intoxication in an adult with intranasal desmopressin therapy for nocturnal enuresis. J Clin Pharmacol 2001 41(5) 582-4. 

An 18-year-old woman presented with new onset seizures and polydipsia. She had a hyponatremia of 117 mmol/1, polyuria for several hours, renal glycosuria with urine glucose of over 55 mmol/1, a blood glucose of 6.6 mmol/1, and solute diuresis. She had low tubular reabsorption of phosphorus, with an appropriate transtubular potassium gradient of 3.0 and a serum potassium of 3.7 mmol/1. After medical treatment and gradual correction of her hyponatremia, her tubular... 

Cerebellovestibular and oculomotor dysfunction (with dizziness, diplopia, nystagmus, ataxia), fatigue, and sedation (usually transient) are relatively common. Nausea, vomiting, cognitive dysfunction, headache, myoclonus (including non-epileptic myoclonus), exacerbation of seizures, movement disorders, behavioral or psychiatric disturbances, hyponatremia, and altered cardiac conduction are less common. 

Tonic-clonic seizures have been reported in four adults who took oral sodium phosphate as Visicol (InKline Pharmaceutical total 40 tablets) for bowel cleansing before colonoscopy (42). None of the patients had a history of seizures or electrolyte abnormahties. In all cases the seizures were associated with electroljde abnormalities, mainly hyponatremia, after administration of Visicol. 

Seizures associated with intravenous use of vinca alkaloids are very rare (60-62). Some cases may have been due to SIADH-associated hyponatremia. Other forms include tumor-related effects, nervous system infections, or cerebral hemorrhage, which often make direct causal relations between drug exposure and nervous system adverse effects very difficult. 

The symptoms of hypocalcemia, usually associated with an acute decrease in serum calcium, include tetany, paresthesias, muscle cramps, and laryngeal spasms. Chronic hypocalcemia is usually associated with the symptoms of depression, anxiety, memory loss, confusion, seizures, hair loss, grooved and brittle nails, and eczema. Associated hypomagnesemia, hypokalemia, and hyponatremia can increase the likelihood of symptoms. 

Infrequent adverse effects of desmopressin spray include nasal irritation, epistaxis, rhinitis, and nasal congestion, whereas desmopressin tablets or spray may cause transient headache, chills, dizziness, nausea, and abdominal pain. Rarely, water intoxication, hyponatremia, and subsequent tonic-clonic seizures have been reported, " particularly in children with concurrent physical disorders, intentional overdoses, or excessive fluid intake. When desmopressin is administered, evening fluids should be limited to 8 ounces to prevent hyponatremia or water intoxication. ... 

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