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PubMedDate not supplied

Prevention of thiazide-induced hypokalemia without magnesium depletion by potassium-magnesium-citrate.

Thiazide can cause magnesium depletion, which may exaggerate renal potassium wasting and hypokalemia. The purpose of this double-blind, randomized trial was to compare the metabolic effects of potassium-magnesium-citrate (K-Mg-citrate) and potassium chloride (KCl) during long-term treatment with thiazide. Twenty-two normal volunteers received hydrochlorothiazide 50 mg/d. Ten subjects concurrently took K-Mg-citrate (42 mEq K/d and 21 mEq Mg/d), and 12 subjects were given KCl 42 mEq/d. Serum potassium concentration remained unchanged during K-Mg-citrate supplementation, with a change from baseline of 21.7% over 6 months, compared with 26.4% with KCl supplementation. Serum electrolytes were normal and not significantly different between K-Mg-citrate and KCl. During K-Mg-citrate treatment, serum magnesium increased significantly by about 10%, associated with an adequate increase in urinary magnesium and a nonsignificant increase in monocyte and free muscle magnesium. Serum magnesium was unchanged, and monocyte and free muscle magnesium showed a nonsignificant decline during KCl supplementation. K-Mg-citrate provided an alkali load, increasing urinary pH, and reducing urinary undissociated uric acid. It also increased urinary citrate and tended to lower the saturation of calcium oxalate. KCl supplementation lacked these actions. K-Mg-citrate prevents thiazide-induced hypokalemia without provoking metabolic alkalosis. It seems to prevent magnesium depletion. By providing an alkali load, it retards the propensity for the crystallization of uric acid and probably of calcium oxalate. Though not conclusive, KCl supplementation may be less effective than K-Mg-citrate in maintaining normokalemia because of a subtle magnesium wasting. Moreover, KCl is devoid of protective action toward crystallization of stone-forming salts.

Acid-Base Equilibrium↗
PubMed2005

The relationship of magnesium intake to serum and urinary calcium and magnesium levels in Trinidadian stone formers.

BACKGROUND: The present study was undertaken to investigate the relationship between the dietary intake of magnesium and the serum and urinary levels of calcium and magnesium in a group of Trinidadian stone formers. METHODS: A group of 102 confirmed stone formers presenting to urological clinics were interviewed using a questionnaire designed to obtain a semi-quantitative estimate of their oral magnesium intake. Patients were invited to give blood samples for serum calcium and magnesium levels and to provide 24-h urine specimens for the measurement of urinary levels of these minerals, as well as total urinary volumes. A group of 102 controls was subjected to a similar interview and blood and urinary testing. Chi-square tests and Student's t-tests were used to examine group demographic differences. The Mann-Whitney test investigated differences in biochemical indices. Binary logistic regression was used to identify predictors of stone formation. RESULTS: Blood samples were obtained from 60 patients and 98 controls. Urine samples were returned by 34 patients and 97 controls. Only 10 stones were retrieved from patients. Patients had a significantly lower magnesium intake, but higher median serum and urinary calcium levels, and higher serum calcium to magnesium ratios than controls. Independent variables capable of predicting stone formation included total magnesium intake and serum and urinary calcium levels. CONCLUSIONS: Increased serum and urinary calcium levels, calcium to magnesium ratios, and a low magnesium intake were predictive of stone formation in this Trinidadian population.

Adult↗
PubMed1998

Reappraisal of the quantity and nature of renal calcifications and mineral metabolism in the magnesium-deficient rat. Effects of treatment with potassium citrate or the combination magnesium citrate and potassium citrate.

There is an urgent need for drugs capable of inhibiting renal calcifications, nephrocalcinosis and stones included, in humans. Current anticalcification medication is based mainly on alkalinization of the metabolism using potassium-containing citrate alone, despite the fact that calcium stone patients suffer marginally from both magnesium and potassium deficiency. We investigated the anticalcification efficacy of oral potassium citrate versus the combined administration of this drug and magnesium citrate in the magnesium-deficient rat developing corticomedullary nephrocalcinosis and luminal microliths in the long term. Among other things we employed specific stains for calcium and oxalate, light microscopy and element analysis for renal tissue and calcifications, respectively. In addition, minerals in renal tissue, urine and plasma were determined, as well as the state of extracellular calcium homeostasis. Magnesium deficiency caused pure calcium phosphate tissue deposits, containing no magnesium, but no deposition of calcium oxalate in the tubular lumen; tissue magnesium, calcium and phosphorus were increased, and there was marked potassium wastage via urine; despite mild hypercalcemia other signs of hyperparathyroidism were not found. Alkalinization with the two kinds of medication evoked an increase in urinary pH, citrate, and potassium; however, potassium citrate alone tended to aggravate renal concretions, whereas the combination of this drug with magnesium citrate completely prevented concretions. It was concluded that: (1) magnesium deficiency-induced calcifications are oxalate-free and are not sensitive to mobilization by alkalinization with potassium citrate, which might explain the failure of the drug to prevent stone recurrence in clinical stone patients, and (2) the combination of potassium citrate and magnesium citrate, which shows enormous anticalcification efficacy, deserves high priority in clinical trials aimed at evaluating strategies for the prevention of stones.

Animals↗
PubMed1988

Oral administration of magnesium hydroxide to subjects with insulin-dependent diabetes mellitus: effects on magnesium and potassium levels and on insulin requirements.

Intra- and extracellular levels of magnesium and potassium were determined in 16 subjects with insulin-dependent type I diabetes mellitus (IDDM) and 30 healthy controls. Subjects with IDDM had lower levels of magnesium in muscle biopsies (p less than 0.001), plasma (p less than 0.001), and mononuclear cells (p less than 0.05), and higher urinary excretions of magnesium (p less than 0.01), and lower levels of potassium in muscle biopsies (p less than 0.001), and erythrocytes (p less than 0.05), as compared with those in controls. Magnesium hydroxide (500 mg/day) was administered orally to the diabetics. The levels of magnesium and potassium in muscle biopsies increased (p less than 0.001; p less than 0.001), while the plasma levels of magnesium and the urinary excretions of magnesium increased only temporarily, during 21 weeks of treatment. The requirements of insulin were reduced (p less than 0.001) during the course of the study, whereas the levels of glycosylated hemoglobin (HbA1c) and glucose were not changed. The findings indicate that administration of magnesium hydroxide is useful to treat muscular magnesium and potassium deficiency in diabetics.

Adult↗
PubMed1985

Influence of vitamin C and magnesium on calcium, magnesium and copper contents of guinea pig tissues.

The effects of a high dose of ascorbic acid superimposed on a low magnesium diet were studied for the first time. Young male guinea pigs were fed for six weeks two diets containing 3000 or 600 ppm magnesium: half in each group was supplemented with a daily oral dose of either 3 mg or 100 mg ascorbic acid per 100 g body weight. No treatment effects were found in serum copper and ceruloplasmin, spleen copper, bone calcium, kidney magnesium, and brain calcium and magnesium contents. Both bone copper and brain ascorbic acid contents of the group fed the normal ascorbic acid/low magnesium diet were lower (p less than 0.01) than the combined means of the other three groups; the high ascorbic acid/low magnesium treatment resulted in normalization of bone copper and brain ascorbic acid levels. Irrespective of ascorbic acid level, the low magnesium diet decreased the bone magnesium and increased the kidney calcium contents (p less than 0.01); this effect on kidney was nearly doubled by the high ascorbic acid intake (p less than 0.01). The results indicated that the main effects were due to the magnesium deficit.

Animals↗
PubMed1978

Survival of normal and magnesium-deficient erythrocytes in rats: effect of magnesium-deficient diet vs. splenectomy.

Magnesium deficiency in rats causes anemia, the mechanism of which is unknown. The effect of dietary magnesium, splenectomy, and magnesium content of erythrocytes on erythrocyte survival was studied in Fisher rats. Half of the animals were splenectomized, the remainder sham-splenectomized; each group was subdivided, and some were placed on a magnesium-deficient diet, the rest on a control diet. After 6 weeks, each of the four subgroups was divided, half were given 51Cr-labeled red cells from magnesium-deficient rats, the remainder, labeled normal red cells. The survival functions of the labeled erythrocytes were fitted to a mathematical model composed of both first-order and accelerating components. The results show that the most important factor influencing erythrocyte survival was dietary magnesium intake. The magnesium content of the transfused red cells affected erythrocyte survival only in the rats fed the control diet, whereas splenectomy affected erythrocyte survival only in rats receiving the magnesium-deficient diet. The accelerating component of the survival function was increased eightfold in the animals fed the magnesium-deficient diet, whereas much smaller changes occurred in the first-order components.

Animals↗
PubMed1993

Studies of magnesium in heart transplantation: further insights into magnesium and cardiac physiology.

Magnesium deficit in man is very difficult to detect and even more difficult to study. However, a chance observation led to the investigation of cardiac transplant recipients as an in vivo model of drug-induced magnesium depletion. Clinical circumstances were such that the question of the correlation of serum and tissue magnesium levels might be addressed. Using the same model, investigation of myocardial calcium levels was undertaken. Significant myocardial magnesium depletion accompanied persistent hypomagnesaemia in over 50 per cent of cardiac transplant recipients. Repletion of myocardial magnesium occurred some weeks later than normalization of serum levels; these time lags may explain the lack of correlation of serum and tissue magnesium levels in these circumstances. Myocardial calcium levels were generally higher than expected from control studies, and were particularly high in magnesium-depleted subjects. These findings are keeping with those predicted from animal studies. Electrophysiological studies in the transplanted denervated heart are free of many of the confounding features of such studies in the native heart. Preliminary work involving pacing protocols designed to induce abnormalities of phase 4 of the action potential suggests that myocardial magnesium deficit does not produce a clinical arrhythmogenic substrate in the denervated heart. However, shortening of the effective ventricular refractory period in hypomagnesaemic patients was observed, and it was noted that concurrent hypokalaemia in this circumstance would be particularly disadvantageous. The data collected in the course of these studies is discussed, and mechanisms for the observed benefit of magnesium as a possible anti-ischaemic agent in the period following acute myocardial infarction are proposed.

Adult↗
PubMed1997

Effects of low calcium and magnesium dietary intake on the central nervous system tissues of rats and calcium-magnesium related disorders in the amyotrophic lateral sclerosis focus in the Kii Peninsula of Japan.

Current epidemiological investigations in the Western Pacific including the Kii Peninsula of Japan, have suggested that environmental factors contribute to the pathogenetic process of amyotrophic lateral sclerosis (ALS) and parkinsonism dementia (PD). The condition of unbalanced minerals (a low content of calcium and magnesium, and a high content of aluminum) found in soil and drinking water in all three ALS foci was experimentally mimicked in our studies using rats. In rat groups maintained on unbalanced mineral diets, the calcium and magnesium contents of bones were lower than those fed a standard diet. In addition, the calcium content of CNS tissues showed higher values in the unbalanced diet groups (especially in the spinal cord of the low calcium and magnesium plus high aluminum diet group) than those in the standard diet group. The calcium content of other soft tissues as well as the CNS of rats fed unbalanced mineral diets was also higher than those on the standard diet. The magnesium content of soft tissues and spinal cord of rats was markedly lower in the low calcium and magnesium plus high aluminum diet group than in the other groups. Examination of tissues from six Kii Peninsula patients with ALS showed an average magnesium concentration in 26 CNS regions (cortical gray matter, white matter, basal ganglia, brain stem, spinal cord) significantly lower than that for five neurologically normal controls. The average calcium concentration in gray matter of ALS cases was significantly higher than that of controls. Interestingly, only 120 cases of calcification of spinal ligaments have been reported worldwide, and of these, 26 of 28 cases of calcification of spinal in the Kii Peninsula have been found to overlap the same geographic focal region as ALS. We analyzed the magnesium content of seven spinal vertebrae and 10 spinal ligaments of patients with calcification of spinal ligaments and the calcium content of five spinal bones compared with controls. The calcification of spinal ligaments patients had lower values for magnesium contents of bones and ligaments compared to controls and the calcium content of bones in these patients was significantly lower than that of controls. These data suggest that low dietary intake of calcium and magnesium over an extended period of time may contribute to the pathogenesis of patients with ALS and calcification of spinal ligaments.

Amyotrophic Lateral Sclerosis↗
PubMed1997

The effects of magnesium physiological supplementation on hyperactivity in children with attention deficit hyperactivity disorder (ADHD). Positive response to magnesium oral loading test.

Children with ADHD are 'a group at risk' as far as their further emotional and social development and educational possibilities are concerned, and the consequences of the lack of an appropriate therapy appears to be serious. Some of these children do not respond to prevailing therapy methods. It is reported that dietetic factors can play a significant role in the etiology of ADHD syndrome, and magnesium deficiency can help in revealing hyperactivity in children. The aim of our work was to assess the influence of magnesium supplementation on hyperactivity in patients with ADHD. The examination comprised 50 hyperactive children, aged 7-12 years, who fulfilled DSM IV criteria for ADHD syndrome, with recognized deficiency of magnesium in the blood (blood serum and red blood cells) and in hair using atomic absorption spectroscopy. In the period of 6 months those examined regularly took magnesium preparations in a dose of about 200 mg/day. 30 of those examined with ADHD showed coexisting disorders specific to developmental age, and 20 of them showed disruptive behaviour. The control group consisted of 25 children with ADHD and magnesium deficiency, who were treated in a standard way, without magnesium preparations. 15 members of this group showed coexisting disorders specific for developmental age, and 10 members showed disruptive behaviour. Hyperactivity was assessed with the aid of psychometric scales: the Conners Rating Scale for Parents and Teachers, Wender's Scale of Behavior and the Quotient of Development to Freedom from Distractibility. In the group of children given 6 months of magnesium supplementation, independently of other mental disorders coexisting with hyperactivity, an increase in magnesium contents in hair and a significant decrease of hyperactivity of those examined has been achieved, compared to their clinical state before supplementation and compared to the control group which had not been treated with magnesium.

Administration, Oral↗
PubMed1991

An evaluation of plasma and erythrocyte magnesium concentration and the activities of alkaline phosphatase and creatine kinase as indicators of magnesium status.

Rats were fed diets containing magnesium at concentrations ranging from 3.3 to 26.7 mmol/kg of diet (80 to 650 mg/kg). The magnesium concentration of their plasma and erythrocytes, and the activities of plasma alkaline phosphatase and creatine kinase were investigated to determine their usefulness as indices of magnesium status. All the indices increased with increasing dietary magnesium levels. The best correlations were observed between dietary intake and plasma concentration of magnesium (r = 0.846, p less than 0.001) and between intake and femur concentration (r = 0.811, p less than 0.001). There was an extremely high correlation between plasma concentration and femur concentration (r = 0.930, p less than 0.001). Although significant, the correlations between intake and the enzyme activities were not strong. It is concluded that plasma magnesium concentration is the most useful indicator of magnesium status and that the activities of the two magnesium-requiring enzymes can only be used for the purpose of diagnosing severely deficient magnesium status.

Alkaline Phosphatase↗
PubMed1999

The bioavailability of magnesium from Wakame (Undaria pinnatifida) and Hijiki (Hijikia fusiforme) and the effect of alginic acid on magnesium utilization of rats.

The bioavailability of magnesium from Wakame and Hijiki, and the effects of alginic acid on absorption of dietary magnesium were examined in five groups of rats fed either control, Wakame, Hijiki, AW (containing the same amount of alginate as in the Wakame) and AH (containing the same amount of alginate as in the Hijiki) diets, and animals fed a low magnesium diet (LMg) (twentieth amount of magnesium in the original mineral mixtures as the control). Food intake and body weight gain were decreased by adding sodium alginate to the diets. A large amount of calcium accumulated only in the kidneys of the rats fed the LMg diet. Serum magnesium concentration decreased only in the LMg group. The magnesium content in the defatted left femurs did not differ between the control and Wakame fed animals and also among the animals eating Wakame, Hijiki and AW diets. The breaking force of the right femurs did not differ among all the groups except the LMg group. The ratio of apparent magnesium absorption (%) of the control, LMg, Wakame, Hijiki, AW and AH groups was 82.2, 72.7, 66.9, 50.8, 69.3 and 54.2 in the first experimental period, and was 75.3, 52.1, 57.7, 46.9, 62.6 and 60.5 in the second experimental period, respectively. It was clear that the bioavailability of magnesium in the Wakame fed rats was higher than in those eating the Hijiki. Large amounts of sodium alginate lowered magnesium absorption from the diet.

Alginates↗
PubMed2003

Magnesium homeostasis in patients undergoing continuous ambulatory peritoneal dialysis: role of the dialysate magnesium concentration.

We carried out this retrospective study to examine the magnesium status of our chronic ambulatory peritoneal dialysis (CAPD) patients dialyzed with 0.75 mmol/L (group I) or 0.50 mmol/L (group II) magnesium peritoneal dialysis solution. A total of 34 anuric patients on CAPD (age:31-72 years; duration of CAPD:7-74 months) were studied. None of them received magnesium-containing phosphate binders or vitamin D. Biochemical parameters including magnesium, calcium, phosphate, parathormone, and albumin were measured in all patients. The corrected for hypoalbuminemia serum magnesium concentration in group I was significantly higher compared to that found in group II. However, there were no significant differences in the other measured parameters between the two groups of CAPD patients, though iPTH levels were somewhat increased in group II patients. Serum magnesium levels were weakly correlated with serum prealbumin levels in both groups of CAPD patients (r=0.16, P=0.08 and r=0.17, P=0.07). The incidence of hypermagnesemia was significantly higher in group I patients versus those in group II (13/19 68.4%] vs. 2/15 13.3%], P<0.01). On the other hand, no patient developed hypomagnesemia (corrected total magnesium <0.65 mmol/L), despite the trend toward decreased magnesium levels in group II patients. Our results point out that serum iPTH levels and nutritional parameters, such as prealbumin levels, should be taken into account in the choice of the magnesium concentration of the peritoneal dialysis fluid.

Adult↗
PubMed1983

Dietary magnesium intake and the concentration of magnesium in plasma and erythrocytes of postpartum women.

Dietary magnesium intakes and concentrations of magnesium in plasma and erythrocytes were determined in 23 lactating and 13 nonlactating healthy pregnant women from 37 wk of gestation through 6 mo postpartum. Food composites, collected for 3 days, were analyzed for magnesium, and energy intake was calculated from 3-day dietary records. The lactating women consumed significantly greater (P less than .05) amounts of magnesium and energy than the nonlactating women. Mean postpartum intake of magnesium was 55% of the recommended dietary allowance (RDA) for lactating women and 48% of the RDA for nonlactating women. Neither lactation nor length of lactation significantly affected plasma magnesium concentration or erythrocyte magnesium concentration. Dietary magnesium intake was not significantly correlated with the level of magnesium in either the plasma or erythrocytes.

Adult↗
PubMed1994

Magnesium homeostasis: conservation mechanism in lactating women consuming a controlled-magnesium diet.

This study was undertaken to determine whether lactating women consuming a low-magnesium diet compensate for magnesium secreted into breast milk by decreasing urinary magnesium losses. Six lactating (L) women, six nonlactating (NL) women (75 +/- 5 and 61 +/- 5 d postpartum, respectively), and seven never-pregnant (NP) women were studied while consuming a constant magnesium intake of 8.97 +/- 0.01 mmol/d for 20 d. After a 5-d stabilization period on the controlled diet, 24-h urine and fecal samples were collected for the next 15 d. The L women excreted significantly less (P < 0.01) urinary magnesium (2.10 +/- 0.35 mmol/d) than the NP women (3.45 +/- 0.37 mmol/d). No significant differences were detected in mean apparent magnesium absorption among the three groups of women, because of large individual variations of fecal magnesium and small sample size. L women apparently compensated for magnesium losses in breast milk (1.04 +/- 0.06 mmol/d) by reducing urinary magnesium losses (1.38 mmol/d) when consuming 8.97 mmol Mg/d.

Absorption↗
PubMed1991

Flash photolysis of magnesium-DM-nitrophen in heart cells. A novel approach to probe magnesium- and ATP-dependent regulation of calcium channels.

Changes in cytoplasmic magnesium concentration in the millimolar range are known to evoke directionally opposite changes in the amplitude of cardiac L-type calcium current, but the effects of magnesium changes in the micromolar range are not known. This concentration range is particularly interesting for two reasons: open-channel block of some ion channels (eg, the inward rectifier) occurs with a micromolar Kd; and magnesium at such low levels may limit the availability of magnesium adenosine triphosphate (MgATP) and magnesium guanidine triphosphate (MgGTP) for a variety of enzymatic processes, including calcium channel phosphorylation. To investigate the effects of critical magnesium depletion and its sudden reversal, we used flash photolysis to liberate magnesium from intracellular DM-nitrophen in guinea pig heart cells. Under our conditions, intracellular [Mg2+] changed from 0.25 mumol/L before the flash to less than or equal to 200 mumols/L afterwards. Calcium channel currents carried by either calcium or barium consistently increased after flash, a directional change opposite to the reported effects of elevated [Mg2+] in the millimolar range. Our data do not yet enable us to understand the basis of the magnesium effect, but we are particularly interested in the possibility that the sudden appearance of magnesium enables calcium channel phosphorylation.

Acetates↗
PubMed1985

1,25 dihydroxyvitamin D3 increases plasma magnesium and calcium in sheep fed liquid diets low in calcium and magnesium.

Sheep given a liquid diet low in calcium and magnesium by infusion directly into the abomasum developed concurrent hypocalcaemia and hypomagnesaemia, with plasma concentrations of calcium and magnesium decreasing to 2.0 and 0.4 mmol/l respectively. Treatment of these hypomagnesaemic sheep with 1,25 dihydroxyvitamin D3 (1,25(OH)2 D3) increased the plasma calcium, magnesium and phosphorus concentrations with plasma calcium increasing to 2.5 mmol/l and plasma magnesium to 0.6 mmol/l. Plasma magnesium increased despite a small but significant increase in the daily excretion of magnesium in the urine, and the amount of magnesium derived from either bone and/or intestine must have been greater than the amount lost in the urine. Since in other experiments we have demonstrated that plasma calcium remains within the normal range when a liquid diet adequate in magnesium but low in calcium is infused, these results imply that either synthesis of and/or end organ response to 1,25(OH2) D3 is impaired in magnesium deficient sheep.

Animal Feed↗
PubMed2004

The influence of magnesium supplementation on concentrations of chosen bioelements and toxic metals in adult human hair. Magnesium and chosen bioelements in hair.

The basic functions of bioelements in biological systems is widely known. Depletion of bioelements and excess of toxic elements lead to impairment of metabolism in the living organism. The existence of magnesium deficiencies in the adult and pediatric populations may cause increased accumulation of toxic metals including lead and cadmium. Prevention of adverse effects of toxic metals may include supplementation with some bioelements and vitamins. The aim of this study was to evaluate the influence of magnesium supplementation on concentrations of chosen bioelements and toxic metals in hair in the adult human population. The research was performed on 124 individuals (53 males and 71 females aged 19-72 years), inhabitants of the city of Szczecin. The concentrations of magnesium, zinc, copper, lead and cadmium were studied in hair. Measurements were performed using the inversion volt-amperometry method with application of an EDD-Tribo PC ETP volt-amperometer. Finally, the supplementation study enrolled 65 individuals with an increased concentration of lead. The studied individuals were divided into two groups: one treated group that enrolled 50 patients who were supplemented with magnesium and the control group that enrolled 15 persons receiving placebo. Finally, supplementation was completed by 32 individuals from the treated group and 10 individuals from the control group. Supplementation was performed using Slow-Mag-B6 preparation at the total daily dose of five tablets divided into 2-3 doses. One tablet contains 535 mg of magnesium chloride i.e. 64 mg of magnesium ions (5.26 mEgMg2) and 5 mg of vitamin B6. Supplementation was performed for a period of 3 months. The remaining individuals did not complete the supplementation due to various reasons; however, none of them resulted from the poor tolerance of the preparation or its adverse events. The results achieved underwent statistical analysis. The results of the study revealed a positive influence of supplementation on concentrations of magnesium and copper in the human body. Supplementation with magnesium caused a statistically significant decrease in concentrations of lead and cadmium. The above mentioned results indicate a positive influence of magnesium supplementation on the decrease of lead and cadmium hair content in the individuals studied.

Adult↗
PubMed1987

The effects of zero magnesium dialysate and magnesium supplements on ionised calcium concentration in patients on regular dialysis treatment.

The effect of oral magnesium carbonate or aluminium hydroxide on serum ionised calcium, total calcium, aluminium and magnesium, was assessed in 31 patients with chronic renal failure, during and after one haemodialysis. The behaviour of ionised calcium and total calcium was the same in both groups. Each showed a slight fall during dialysis, which was not significant. Serum total calcium was 0.2-0.3 mmol/l (0.8-1.2 mg/dl) greater throughout the period of dialysis in the group taking aluminium hydroxide. Serum magnesium and aluminium were both lower in the group treated with magnesium carbonate. In the group taking magnesium carbonate, serum magnesium concentrations fell markedly during dialysis, but otherwise were maintained within the reference range by the use of a magnesium-free dialysate. These results show the effectiveness of magnesium carbonate oral phosphate-binding agents and zero magnesium dialysate in reducing serum aluminium without affecting the behaviour of serum calcium fractions during dialysis.

Administration, Oral↗