Magnesium oxide and hydroxide react quickly with gastric HC1, but cause diarrhoea, as do all magnesium salts (which are also used as purgatives). Magnesium carbonate is rather less effective.
Magnesium trisilicate reacts slowly, to form magnesium chloride, which reacts with intestinal secretions to form the carbonate: chloride is liberated and reabsorbed. Systemic acid-base balance is thus not significantly altered.
Aluminium hydroxide reacts with HC1 to form aluminium chloride; this in turn reacts with intestinal secretions to produce insoluble salts, especially phosphate. The chloride is released and reabsorbed so systemic acid-base balance is not altered. It tends to constipate. Sufficient aluminium may be absorbed from the intestine to create a risk of encephalopathy in patients with chronic renal failure. Hypophosphataemia and hypophosphaturia may result from impaired absorption due to phosphate binding.
Sodium bicarbonate reacts with acid and relieves pain within minutes. It is absorbed and causes
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Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...