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Magnesium and Seizures | |
Note: The following abstracts are written in extremely technical language and include technical research and case studies. References are provided. For 'user-friendly' informative reading, check out the health topics presented by Dr. Martin and Dr. Davenport. Feel free to contact us for more information or if you have any questions.
NMDA receptor complex blockade by oral administration of magnesium: comparison with MK-801
The ion channel of the N-methyl-D-aspartate (NMDA) receptor complex is subject to a voltage-dependent regulation by Mg2+ cations. Under physiological conditions, this channel is supposed to be blocked by a high concentration of magnesium in extracellular fluids. A single dose of magnesium organic salts (i.e., aspartate, pyroglutamate, and lactate) given orally to normal mice rapidly increases the plasma Mg2+ level and reveals a significant dose-dependent antagonist effect of magnesium on the latency of NMDA-induced convulsions; this effect is similar to that seen after administration of the dizocilpine (MK-801) channel blocker. An anticonvulsant effect of Mg2+ treatment is also observed with strychnine-induced convulsions but not with bicuculline-, picrotoxin-, or pentylenetetrazol-induced convulsions. In the forced swimming test, Mg2+ salts reduce the immobility time in a way similar to imipramine and thus resemble the antidepressant-like activity of MK-801. This activity is masked at high doses of magnesium by a myorelaxant effect that is comparable to MK-801-induced ataxia. Potentiation of yohimbine fatal toxicity is another test commonly used to evaluate putative antidepressant drugs. Administration of Mg2+ salts, like administration of imipramine strongly potentiates yohimbine lethality in contrast to MK-801, which is only poorly active in this test. Neither Mg2+ nor MK-801 treatment can prevent reserpine-induced hypothermia. These data demonstrate that oral administration of magnesium to normal animals can antagonize NMDA-mediated responses and lead to antidepressant-like effects that are comparable to those of MK-801. This important regulatory role of Mg2+ in the central nervous system needs further investigation to evaluate the potential therapeutic advantages of magnesium supplementation in psychiatric disorders.
Decollogne-S; Tomas-A; Lecerf-C; Adamowicz-E; Seman-M
Pharmacol-Biochem-Behav. 1997 Sep; 58(1): 261-8
Recent advances in the management of preeclampsia
The past decade has been characterized by few advances regarding the pathophysiology and prevention but many changes in the clinical treatment of patients with preeclampsia. Specifically, recommendations have been made for home or day-care management of a select group of patients with mild gestational hypertension or preeclampsia. Moreover, three randomized clinical trials revealed that expectant management with close monitoring of maternal and fetal conditions is possible in a select group of patients with severe preeclampsia at less than 34 weeks' gestation. In addition, the efficacy of magnesium sulfate in the prevention and control of eclamptic convulsion has been validated in randomized controlled trials performed worldwide. In contrast, recent randomized trials failed to demonstrate any major benefit from the routine use of low-dose aspirin in pregnancy, whereas a recent meta-analysis found calcium supplementation during pregnancy to be effective in reducing the risk of hypertension.
Lewis-R; Sibai-B
J-Matern-Fetal-Med. 1997 Jan-Feb; 6(1): 6-15
Hypocalcemia and hypomagnesemia after ibuprofen overdose
OBJECTIVE: To report a case of hypocalcemia and hypomagnesemia after ibuprofen overdose. CASE SUMMARY: A 21-month-old boy developed acute renal failure with severe metabolic acidosis after ingestion of ibuprofen 8 g. The infant developed tonic-clonic seizures 46 hours after ingestion, with significant hypocalcemia and hypomagnesemia that required electrolyte replacement to control the seizures.
DISCUSSION: To our knowledge this is the first case report of hypocalcemia, hypomagnesemia, and seizures in a patient after ibuprofen overdose. The mechanism is unclear, the situation was probably aggravated by the use of sodium polystyrene sulfonate and furosemide.
CONCLUSIONS: In patients with ibuprofen overdose, serum calcium and magnesium concentrations should be evaluated since seizures may be associated with a deficiency of these cations. The management of these patients should include calcium and/or magnesium supplementation when required and furosemide should be avoided.
al-Harbi-NN; Domrongkitchaiporn-S; Lirenman-DS
Ann-Pharmacother. 1997 Apr; 31(4): 432-4
Primary infantile hypomagnesaemia: report of two cases
OBJECTIVE: To present case reports of two siblings with primary hypomagnesaemia both presenting with seizures, and one also with a cardiac arrhythmia. To briefly review the pathophysiology, clinical features, diagnosis, management and genetics of this disorder. METHODOLOGY: Published literature reports of primary hypomagnesaemia and studies of hypomagnesaemia in humans. Reports of the clinical features and inheritance of primary hypomagnesaemia. RESULTS: The information is descriptive of the pathophysiology, clinical features, diagnostic criteria, and management. Considered modes of inheritance are presented. Two cases of primary hypomagnesaemia in brothers of consanguineous parents are described. Cardiac arrhythmia at presentation has not previously been reported. Diagnosis and adequate magnesium supplementation controls the biochemical disorder and the neurological development is normal. CONCLUSIONS: Primary hypomagnesaemia should be considered in infants with seizures, as failure to identify this metabolic disorder can result in death. Subsequent siblings, particularly male, should be closely monitored.
Prebble-JJ
J-Paediatr-Child-Health. 1995 Feb; 31(1): 54-6
Brain and CSF magnesium concentrations during magnesium deficit in animals and humans: neurological symptoms
Magnesium is an essential cofactor for many enzymatic reactions, especially those involved in energy metabolism. Deficits of magnesium are prevalent due to inadequate intake or malabsorption and due to the renal loss of magnesium that occurs in certain disease states (alcoholism, diabetes) and with drug therapy (diuretics, aminoglycosides, cisplatin, digoxin, cyclosporin, amphotericin B). Protracted deficits of magnesium in humans and animals result in neurological disturbances, including hyperexcitability, convulsions and various psychiatric symptoms ranging from apathy to psychosis, some of which can be reversed with magnesium supplementation, others requiring correction of the dysregulation mechanism. Although the role of magnesium in neuronal function is not completely understood, a lowering of CSF or brain magnesium can induce epileptiform activity and there is an association between decreased CSF magnesium and the development of seizures. CSF concentrations of magnesium are normally higher than magnesium plasma ultrafiltrate (diffusible) concentrations due to the active transport of magnesium across the blood-brain barrier. Under conditions of magnesium deficiency, CSF concentrations decline, although this decline lags behind and is less pronounced than the changes observed in plasma magnesium concentrations. Decreases in CSF magnesium concentrations correlate with the alterations observed in extracellular brain magnesium concentrations in animals following the dietary deprivation of magnesium. CSF magnesium concentrations can readily be repleted following magnesium supplementation, although high dose magnesium therapy, such as that used in the treatment of convulsions in eclampsia, will only increase CSF magnesium concentrations to a very limited degree (approximately 11-18 per cent) above physiological concentrations. Greater increases in CSF magnesium may occur in neonates since neonatal swine, following treatment with magnesium, have CSF magnesium concentrations that are similar to their plasma concentrations. There has been a recent resurgence of interest in magnesium deficiency and its neurological consequences due to the finding that magnesium, at physiological concentrations, blocks N-methyl-D-aspartate (NMDA) receptors in neurones. NMDA receptors are normally activated by glutamate and/or aspartate which represent the principal neurotransmitters for excitatory synaptic transmission in vertebrate CNS. Magnesium deficiency produces epileptiform activity in the CNS which can be blocked by NMDA receptor antagonists. Other mechanisms, including alterations in Na+/K(+)-ATPase activity, cAMP/cGMP concentrations and calcium currents in pre- and postsynaptic membranes, may also be at least partially responsible for the neuronal effects associated with low brain magnesium. Further studies are necessary to increase our understanding of the neurological implications of magnesium deficit in the central nervous system.
Morris-ME
Magnes-Res. 1992 Dec; 5(4): 303-13
Severe renal osteodystrophy without elevated serum immunoreactive parathyroid hormone concentrations in hypomagnesemia due to renal magnesium wasting
An 8 1/2-year-old girl presented with a long history of seizures, growth retardation, muscle weakness, gait disturbance, and hearing loss. Her evaluation revealed chronic moderate renal failure (serum creatinine 2.2 mg/dL), severe hypocalcemia (5 mg/dL), hyperphosphatemia (8.1 mg/dL), hypomagnesemia (1.5 mg/dL), increased urinary magnesium excretion (2 mg/kg/d), high fractional excretion of magnesium (21.7%), hypokalemia (3.2 mEq/L), and hyperkaliuria (26 mEq/L). Low circulating immunoreactive parathyroid hormone levels for the degree of the hypocalcemia (serum N-parathyroid hormone 212 pg/mL) and severe rickets without evidence of osteitis fibrosa cystica were found. The patient probably has primary renal leak hypomagnesemia (magnesuric hypomagnesemia) which caused impaired secretion of immunoreactive parathyroid hormone leading to severe hypocalcemia and calcium deficiency rickets. Treatment with magnesium and calcium supplements, calcitriol, and aluminum hydroxide resulted in marked clinical, biochemical, and radiologic improvement. Calcium deficiency rickets due to primary or secondary renal magnesium wasting in conjunction with moderate renal failure represents a largely unrecognized metabolic bone disease.
Zelikovic-I; Dabbagh-S; Friedman-AL; Goelzer-ML; Chesney-RW
Pediatrics. 1987 Mar; 79(3): 403-9
Primary hypomagnesemia with secondary hypocalcemia. Report of a case and review of the world literature
Primary hypomagnesemia with secondary hypocalcemia (PHSH) is a rare type of hypocalcemic disorder which occurs in early infancy and is clinically characterized by recurrent tetany and/or convulsion. In this paper, a male infant with PHSH who had frequent seizures at the age of 9 days is described. Besides PHSH, several illnesses in infancy are manifested by hypomagnesemia and hypocalcemia, i.e. transient neonatal hypomagnesemic hypocalcemia, congenital renal or hepatic insufficiencies, magnesium-losing nephropathy, combined impairments of intestinal absorption and renal reabsorption of magnesium. PHSH is to be differentiated from these illnesses by the demonstration of a combination of the following findings; hypocalcemia refractory to calcium but responsive to magnesium, continuous requirement for magnesium supplementation to maintain normocalcemia, lack of hypermagnesiuria and/or impaired intestinal absorption of magnesium. Twenty cases from the literature were found to exhibit these characteristics. The clinical, biochemical, and endocrine features of PHSH are summarized on the basis of a review of the data of these and the present case. No associated illness was known in the afflicted infants or mothers. Both male and female infants were afflicted at a male to female ratio of 15:6. Some siblings were afflicted but none of the parents or relatives. The onset of tetany and/or convulsion was between the 9th day and 4th month, which is later than that of other neonatal hypocalcemic illnesses. Hypocalcemia was more pronounced than other infantile hypocalcemic illnesses. The role of the parathyroid hormone in the pathogenesis of hypocalcemia has been studied in several studies but no unifying concepts have yet been established.
Yamamoto-T; Kabata-H; Yagi-R; Takashima-M; Itokawa-Y
Magnesium. 1985; 4(2-3): 153-64
Concurrent renal hypomagnesemia and hypoparathyroidism with normal parathormone responsiveness
A 24-year-old woman presented with clinical features suggesting hypoparathyroidism: tetany, basal ganglia calcification, and a history of a seizure disorder. Hypocalcemia was present on admission despite therapy with calcium and vitamin D. Hormonal evaluation revealed undetectable parathormone levels and a normal cyclic AMP and phosphaturic response to parathormone infusion, suggesting the diagnosis of idiopathic hypoparathyroidism. Additional testing, however, revealed hypomagnesemia and elevated urinary magnesium levels. Normomagnesemia could not be consistently achieved despite oral magnesium administration. When the serum magnesium level was temporarily normalized via intravenous magnesium supplementation, parathormone levels rose into the normal range. These data indicate that the patient's hypomagnesemia was most likely due to renal magnesium loss. The normalization of her parathormone level during magnesium replenishment, along with the parathormone infusion data, suggests that this patient's hypomagnesemia was responsible for decreased parathormone synthesis and/or secretion, while target tissue responsiveness to parathormone was maintained.
Duran-MJ; Borst-GC 3d; Osburne-RC; Eil-C
Am-J-Med. 1984 Jan; 76(1): 151-4
