Methylprednisolone modulates intracranial pressure in the brain cellular edema induced by water intoxication.

Continuous monitoring of the intracranial pressure (ICP) detects impending intracranial hypertension resulting from the impaired intracranial volume homeostasis, when expanding volume generates pressure increase. In this study, cellular brain edema (CE) was induced in rats by water intoxication (WI). Methylprednisolone (MP) was administered intraperitoneally (i.p.) before the start of CE induction, during the induction and after the induction. ICP was monitored for 60 min within 20 h after the completion of the CE induction by fibreoptic pressure transmitter. In rats with induced CE, ICP was increased (Mean+/-SEM: 14.25+/-2.12) as well as in rats with MP administration before the start of CE induction (10.55+/-1.27). In control rats without CE induction (4.62+/-0.24) as well as in rats with MP applied during CE induction (5.52+/-1.32) and in rats with MP applied after the end of CE induction (6.23+/-0.73) ICP was normal. In the last two groups of rats, though the CE was induced, intracranial volume homeostasis was not impaired, intracranial volume as well as ICP were not increased. It is possible to conclude that methylprednisolone significantly influenced intracranial homeostasis and thus also the ICP values in the model of cellular brain edema.

NMDA receptor-antagonistic properties of hyperforin, a constituent of St. John's Wort.

Extracts of the medicinal plant St. John's wort (Hypericum perforatum) are widely used for the treatment of affective disorders. Hyperforin, a constituent of St. John's wort, is known to modulate the release and re-uptake of various neurotransmitters, an action that likely underlies its antidepressive activity. We now report that hyperforin also has N-methyl-D-aspartate (NMDA)-antagonistic effects. Hyperforin (10 microM) was found to inhibit the NMDA-induced calcium influx into cortical neurons. In rat hippocampal slices, hyperforin inhibited the NMDA-receptor-mediated release of choline from phospholipids. Hyperforin also antagonized the increase of water content in freshly isolated hippocampal slices, and it counteracted, at 3 and 10 microM, the increase of water content induced by NMDA. Hyperforin was inactive, however, in two in vivo models of brain edema formation, middle cerebral artery occlusion and water intoxication in mice. In conclusion, hyperforin has NMDA-receptor-antagonistic and potential neuroprotective effects in vitro. This effect may contribute to the therapeutic effectiveness of St. John's wort extracts in some situations, for example, for relapse prevention in alcoholism.

Successful treatment of polydipsia, water intoxication, and delusional jealousy in an alcohol dependent patient with clozapine.

The beneficial effect of clozapine on polydipsia and water intoxication in patients with schizophrenia has been demonstrated many times. The authors report a successful clozapine treatment of polydipsia, intermittent water intoxication, and delusional jealousy of an alcoholic. This is a rare case of clozapine treatment of a non-schizophrenic patient affected by polydipsia.

Self-induced water intoxication treated with risperidone.

OBJECTIVE: To determine whether or not risperidone is efficacious in treating self-induced water intoxication in patients with chronic schizophrenia. METHOD: We carried out a prospective 11-month open-label study using risperidone to treat 8 men with chronic schizophrenia and self-induced water intoxication. RESULTS: The 8 men were not able to reduce their fluid consumption compared with their baseline intake. Risperidone, however, significantly decreased the Brief Psychiatric Rating Scale (BPRS) scores of this very chronic group. CONCLUSIONS: Although risperidone decreased schizophrenic symptoms, it did not have significant efficacy in treating self-induced water intoxication. This study may have implications for the treatment of addictive behaviour.

[Water intoxication following preparation for barium enema]. / Intoxication par l'eau après une préparation pour un lavement baryté.

BACKGROUND: Induction of water intoxication from tap water enemas was reported a few years ago. Its treatment is still debated. CASE REPORT: A 4 1/2 year-old boy was admitted because he suffered from coma grade I. A barium enema had been prescribed for fecal incontinence and the patient had been given orally about 4 liters of water during the 24 hours preceding this investigation. Blood examination showed;: Na 122 mEq/l; K 3 mEq/l; Cl 87 mEq/l. Brain CT scan was normal. The patient was placed under restriction of fluid and was given i.v. 5.8% NaCl solution (2 mM/kg) for 3 hours. Convulsions appeared despite this treatment requiring intubation and ventilation plus increasing doses of NaCl: 20% solution (2 mM/kg) for 30 minutes followed by 2 mM/kg for 3 hours, associated with mannitol and furosemide infusion. CONCLUSION: Use of hypertonic saline solutions in the treatment of water intoxication is discussed. Acute hyponatremia must be rapidly corrected using hypertonic saline solution plus restriction of fluid and diuretic.

Serum sodium stabilizing effect of enalapril after standard water load in a patient with a history of self-induced water intoxication.

1. A 21 day prospective placebo controlled double blind cross over trial of enalapril was studied in a normonatremic patient with a known history of SIWI. 2. At the end of each prophylactic treatment, the patient was challenged with a water load of 20 ml/kg. 3. The mean serum sodium of 140.111 mmol/L on prophylactic enalapril was significantly higher than the 137.6 mmol/L on placebo (p = 0.0015). 4. After a water load, the mean serum sodium on enalapril was 137.6 mmol/L, compared to 133.833 mmol/L (p = 0.0015) on placebo.

Perspective on carbamazepine-induced water intoxication: reversal by demeclocycline.

Carbamazepine (CBZ)-induced water intoxication occasionally limits its usefulness in refractory seizures and trigeminal neuralgia. Fluid restriction, CBZ dose reduction, or concomitant phenytoin therapy may be impractical or ineffective. Demeclocycline (7-chloro-6 demethyl tetracycline) (DMC) corrected the CBZ-induced water intoxication in a 51-year-old man with refractory complex partial seizures and a normal antidiuretic hormone (ADH) level. DMC inhibits ADH-sensitive adenylate cyclase activity in the renal collecting duct and may be useful in correcting the ADH-like or renal antidiuretic effect of CBZ.

Partial reversal of carbamazepine-induced water intolerance by demeclocycline.

The anti-diuretic action of carbamazepine, before and after concurrent treatment with demeclocycline, has been studied in a single epileptic subject, in whom two episodes of status epilepticus had been associated with excessive fluid intake and hyponatraemia. After addition of demeclocyline, free water clearance, plasma arginine vasopressin concentration and serum osmolality (all appreciably reduced after carbamazepine alone) increased but did not revert to normal. The findings are consistent with direct antagonism by demeclocycline of the enhancing effect of carbamazepine on endogenous ADH activity.

[Effect of diazepam and phenazepam on Leao's depression in brain edema]. / Vliianie diazepama i fenazepama na depressiiu Leao pri oteke golovnogo mozga.

Experiments on rats with brain edema under water intoxication were made to examine the effect of the benzodiazepine tranquilizers diazepam and phenazepam on the time course of the recovery of brain electrical activity after passing the spreading Leao's depression wave. It was found that the drugs indicated possess antiedematous properties and improve brain function under these conditions. It is assumed that the drug action on the spreading depression is linked with their effect on metabolic processes in the brain and antiedematous properties.

Compulsive water drinking treated with high dose propranolol.

A patient with recurrent, life-threatening water intoxication secondary to compulsive water drinking is described. This patient responded well to nearly 1 g of propranolol daily with a decrease in her drinking behavior, reduced sensation of thirst, and a reduction in her delusional thinking. The rationale for the choice of propranolol with this patient is reviewed.

Rapid correction of water intoxication by hypertonic saline and frusemide.

A case of profound hyponatraemia with severe cerebral dysfunction, induced by excess water intake and exacerbated by smoking, is described. Rapid correction with hypertonic saline infusions and frusemide allowed a negative fluid balance and elevation of serum sodium concentration to be achieved without precipitating acute pulmonary oedema.