Magnesium hydroxides Subject

Wallace KL, Curry SC, LoVecchio F, Raschke RA. Effect of magnesium hydroxide on iron absorption following simulated mild iron oversdose in human subjects. Acad Emerg Med 1998 5(10) 961-5. 

Rgure 10.10 Plasma levels of bishydroxycoumarin (BHC), also known as dicoumarol, in 6 subjects after a 300 mg oral dose with water (solid line), magnesium hydroxide (dotted line) or aluminium hydroxide (dashed line). Closed data points represent a significant difference from control. 

In 10 healthy subjects an antacid containing aluminium/magnesium hydroxide and magnesium carbonate reduced the AUC of a single 50-mg dose of captopril by about 40%, when compared with the fasting state. However, this did not alter the extent of the reduction in blood pressure. ... 

The absorption of mefenamic acid and tolfenamic acid is markedly accelerated by magnesium hydroxide in fasted subjects. The rate of tolfenamic acid absorption is reduced by aluminium hydroxide alone or combined with magnesium hydroxide/magnesi-um carbonate, but is not affected by sodium bicarbonate. 

In 24 healthy subjects an aluminium/magnesium hydroxide antacid (Maalox) had no effect on the rate or extent of absorption of a single 25-mg dose of dexketoprofen, although the maximum level was slightly (13%) lower. ... 

Sodium bicarbonate 700 mg or 1.4 g increased the rate of absorption of a single 300-mg dose of naproxen in 14 healthy fasted subjects, whereas magnesium oxide or aluminium hydroxide 700 mg had the opposite effect, and reduced the rate of absorption. Magnesium carbonate had little effect. On the other hand when 15 or 60 mL of aluminium/magnesium hydroxide (Maalox) was given, the rate and extent of absorption of naproxen were slightly increased. ... 

In another single-dose study in 6 healthy, fasted subjects, aluminium hydroxide suspension 700 mg reduced the rate of indometacin absorption, and reduced the peak indometacin plasma levels. Conversely, sodium bicarbonate 1.4 g appeared to increase the rate of absorption, but this did not reach significance because of wide inter-individual variation. In a further study 30 mL of aluminium/magnesium hydroxide caused only slight changes in the absorption of a 50-mg dose of indometacin in fasted subjects. ... 

The AUC of oral ketorolae 10 mg was found to be reduced by 11% (not statistically significant) when taken with an unstated amount of aluminium/magnesium hydroxide suspension (Maalox) in 12 healthy fasted subjects. The rate of absorption was not affected. ... 

A pharmacokinetic study in 24 healthy, fasted subjects showed that aluminium/magnesium hydroxide suspension Maalox), given as a single 20-mL dose four times daily for 3 days, had no significant effect on the absorption of a single 400-mg dose of tolmetin. ... 

Neither 10 mL of Maalox (aluminium/magnesium hydroxide) nor 10 g of Solugastril (aluminium hydroxide with calcium carbonate) had any effect on the pharmacokinetics of a 4-mg lomoxicam film-coated tablet in 18 healthy fasted subjects. A later study similarly found no changes in the absorption or pharmacokinetics of a lomoxicam film-coated tablet given with bismuth chelate (tripotassium dicitratobismuthate) 120 mg twice daily. There would seem to be no reason for avoiding concurrent use. 

In an open, randomised, crossover study 9 healthy, fasted subjects were given meloxicam 30 mg alone or with Maalox suspension (aluminium/magnesium hydroxide 900/600 mg) four times daily for 4 days. Maalox had no significant effect on the pharmacokinetics of the meloxi-cam. Therefore no adjustments of the dosage of meloxicam are needed if given with this type of antacid. 

A multiple-dose study in 20 healthy subjects found that A/y/an/a (aluminium/magnesium hydroxide) aaAAmphojel (aluminium hydroxide) did not significantly affect the bioavailability of piroxicam 20 mg daily taken after food. Concurrent use need not be avoided. 

The bioavailability of tenoxicam 20 mg was found to be unaffected in 12 healthy subjects by aluminium hydroxide (Amphojel) or aluminium/magnesium hydroxide Mylanta) whether taken before, with, or after the tenoxicam, and in the fasted state or with food. No special precautions seem necessary. 

A study in 12 healthy subjects found thatMylanta (aluminium/magnesium hydroxide) 20 mL did not significantly affect the bioavailability of a single 200-mg dose of posaconazole, either when taken with food or when fasting. ... 

The AUC and maximum level of metrifonate and its pharmacologically active metabolite were not altered by concurrent use of an aiuminium/magnesium hydroxide-containing antacid in a single-dose study in healthy subjects. ... 

A study in 12 healthy subjects found that pretreatment with alumini-um/magnesium hydroxide (Maalox) 30 mL (10, 2 and 0.5 hours before dofetilide) did not affeet the pharmacokinetics of a single 500-microgram dose of dofetilide, nor the dofetilide-induced change in QTc interval. No speeial preeautions appear to be necessary. 

A patient on quinidine who took eight Afy/ow/a tablets daily (aluminium hydroxide gel 200 mg, magnesium hydroxide 200 mg and simeticone 20 mg) for a week and a little over 1 litre of fruit juice (orange and grapefruit) each day developed a threefold increase in serum quinidine levels (from 8 to 25 mg/L) and toxicity. However, note that the grapefruit juice , (p.280) may have contributed. In 6 healthy subjects, this dose oiMylanta for 3 days produced consistently alkaline urine in 4 subjects, and in 5 subjects when combined with fruit juice. ... 

A study with cefaclor AF (a formulation with a slow rate of release) found that an aluminium/magnesium hydroxide antacid (Maalox) given one hour after the cefaclor AF to fed subjects reduced the AUC by 18%. This reduction is small and unlikely to be clinically important. 

A study in 10 healthy subjects found that 10 mL of an aluminium/magnesium hydroxide antacid (Maalox) reduced the bioavailability of cefpodoxime proxetil by about 40%. This was considered to be due to reduced dissolution at increased gastric pH values. These results confirm the findings of a previous study with sodium bicarbonate and aluminium hydroxide. It has been recommended that cefpodoxime is given at least 2 hours after antacids. ... 

In 18 healthy subjects, 60 mL of an antacid containing aluminium/magnesium hydroxide plus simeticone (Atlanta IT) was found not to affect the pharmacokinetics of ceftibuten 400 mg. ... 

A study in 12 healthy subjects found that the bioavailability of a single 500-mg dose of cycloserine was not affected by 15 mL oiMylanta (aluminium hydroxide 400 mg, magnesium hydroxide 400 mg, simeticone 40 mg per 5 mL). Mylanta was given 9 hours before the eyeloserine, at the same time as the cycloserine, immediately after meals, and at bedtime on the dosing day and following day. ... 

A study in healthy subjects found thatMaafox 70mValsuspension 10 mL (aluminium/magnesium hydroxide) did not affect the pharmacokinetics of a single 600-mg dose of linezolid. ... 

A crossover study in 6 healthy subjects confirmed that aluminium hydroxide gel does not affect the absorption of nitrofurantoin from the gut (as measured by its excretion into the urine). Another study in 10 healthy subjects found that an antacid containing aluminium hydroxide, magnesium carbonate and magnesium hydroxide reduced the absorption of nitrofurantoin by 22%. ... 

In 14 healthy subjects 30 mL of MylaiUa (aluminium/magnesium hydroxide) given 9 hours before, with, and after a single 30-mgZkg dose of pyrazinamide decreased the time to peak absorption by 17%, but had no effect on other pharmacokinetic parameters. This change is not clinically important. 

Magnesium hydroxide (Milk o/Magnesia) 15 mL taken with and 3 hours after a single dose of dicoumarol was found to raise the peak plasma levels and AUC of dicoumarol by 75% and 50%, respectively, in 6 healthy subjects. Conversely, aluminium hydroxide (Amphogel) 30 mL did not alter dicoumarol levels. ... 

A placebo-controlled study found that 10 mL of Maalox 70 (alumini-IIIII magnesium hydroxide) had no effect on the blood glucose-and insulin-lowering efifeets of aearbose 100 mg in24 healthy subjects given a 75-g dose of sucrose. It was concluded that no special precautions are needed if this or similar antacids are used with acarbose. ... 

Magnesium hydroxide 850 mg increased the rate of absorption of chlorpropamide 250 mg in healthy subjects, but the insulin and glucose responses were unaffected. ... 

Elsewhere, 2 epileptie patients are reported to have had inadequate seizure eontrol, which coincided with the ingestion of aluminium/magnesi-um hydroxide antacids for dyspepsia. The AUC of a single dose of phenytoin was reduced by about 25% in 8 healthy subjects given either aluminium/magnesium hydroxide or caicium carbonate. ... 

In a study in 12 healthy subjects the extent of absorption of a single 250-mg dose of ticlopidine was increased by 20% and occurred more rapidly when ticlopidine was taken after food, when compared with the fasting state. In contrast, 30 mL of Maalox [aluminium/magnesium hydroxide] reduced the extent of ticlopidine absorption by about 20%. These modest changes are unlikely to be of much clinical importance. 

A study in 6 healthy subjects found that the bioavailability of a single 100-mg dose of sulpiride was reduced by 40% by sucralfate 1 g and by 32% by 30 mL of Simeco (aluminium/magnesium hydroxide and simeticone). When either the sucralfate or the antacid were taken 2 hours before sulpiride the reduction in bioavailability was only about 25%, and no change in hioavailahility was seen in one subject when the sucralfate was given 2 hours after the sulpiride. ... 

---