Drug information of Aluminium hydroxide

Aluminium hydroxide

Drug group:

Aluminum hydroxide is an inorganic salt used as an antacid. It is a basic compound that acts by neutralizing hydrochloric acid in gastric secretions. Subsequent increases in pH may inhibit the action of pepsin. An increase in bicarbonate ions and prostaglandins may also confer cytoprotective effects.

Mechanism of effect

Aluminum hydroxide is a basic inorganic salt that acts by neutralizing hydrochloric acid in gastric secretions. Aluminum hydroxide is slowly solubilized in the stomach and reacts with hydrochloric acid to form aluminum chloride and water.

It also inhibits the action of pepsin by increasing the pH and via adsorption. Cytoprotective effects may occur through increases in bicarbonate ion (HCO3-) and prostaglandins.


Gastric-peptic disease occurs as a result of an imbalance between protective factors, such as mucus, bicarbonate, and prostaglandin secretion, and aggressive factors, such as hydrochloric acid, pepsin, and Helicobacter pylori (H. pylori).

Antacids work by restoring acid-base balance, attenuating the pepsin activity and increasing bicarbonate and prostaglandin secretion.



Bioavailability: only relatively small amounts are absorbed gastrointestinally

Onset: 5 to 10 minutes

Duration: 100 minutes


Half-life: 18-24 hr; up to 36 hr with advanced age or renal impairment

Dialyzable: Yes (hemodialysis, 50-90 mL/min; peritoneal dialysis, 13-15 mL/min)

Renal clearance: 20-40 mL/min

Excretion: Urine (95-99%)

Drug indications

indigestion , Duodenal Ulcer


oral suspension

  • 320mg/5mL 



5-30 mL PO between meals and HS or as directed

Peptic Ulcer Disease

5-30 mL between meals and HS or as directed


300-600 mg PO 3 times/day between meals and HS 



50-150 mg/kg/day PO divided q4-6hr; titrate dose to keep phosphorus within normal range


  • Aluminum toxicity may occur in renal failure patients
  • Hypophosphatemia may occur
  • Use caution in patients with heart failure, cirrhosis, edema, or renal failure
  • Will bind calcium if given at same time
  • Elderly may be predisposed to fecal impaction
Use caution in patients who have recently suffered massive gastrointestinal hemorrhage

Points of recommendation

Tell patient to report symptoms of heartburn or acid indigestion that persist for more than 2 weeks.
- Side effects may include diarrhea.
- Instruct patient not to exceed maximum adult dose in 24-hour period or use of maximum dose for more than 2 weeks.

Pregnancy level


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