Antiacid , Antihyperphosphatemic
Each tablet contains Aluminum hydroxide 300 mg
Al ( OH ) 3
Absorption : small amounts of the aluminum in aluminum hydroxide are absorbed from the intestine .
Onset and duration of action : Slow , prolonged
Elimination : Renal and fecal ; 15 to 30 % of the salts formed are absorbed and are then excreted by the kidneys.
Mechanism of action :
- Antacid – these medications react chemically to neutralize or buffer existing quantities of stomach acid but have no direct effect on its output. This action results increased pH value of stomach contents , thus providing relief of hyperacidity symptoms . Also , these medications reduce acid concentration within the lumen of the esophagus . This causes an increase in intra-esophageal pH and a decrease in pepsin activity .
- Antihyperphosphatemic – Aluminum hydroxide reduce serum phosphate levels by binding with phosphate ions in the intestine to form insoluble aluminum phosphate , which passes through the intestinal tract unabsorbed .
- Antihypocalcemic – Aluminum hydroxide may increase the release of calcium from bone as a result of the decreased serum phosphate levels .
- Antidiarrheal – Aluminum hydroxideۥs constipating properties help decrease the fluidity of stools .
Indications and usage :
- For Antacid use : the dose of antacid needed to neutralize gastric acid varies among patients , depending on the amount of acid secreted and the buffering capacity of the particular preparation . It is estimated that 99% of the gastric acid will be neutralized when a gastric pH of 3.3 is achieved .
- For use in peptic ulcer : In the treatment of peptic ulcer disease , to achieve adequate antacid effect in the stomach at the optimum time , most antacids are administered 1 and 3 hours after meals for prolonged acid-neutralizing effect and at bedtime.However,when taken at bed time , their affect is not prolonged because of rapid gastric emptying. Additional doses of antacids may be administered to relieve the pain that may occur between the regularly scheduled doses. Antacid therapy should be continued for at least 4 to 6 weeks after all symptoms have disappeared , since there is no correlation between disappearance of symptoms and actual healing of the ulcer .
- For antihyper phosphatemic use .
– This medication should not be used when intestinal obstruction exist .
– Risk-benefit should be considered when the following medical problems exist :
1) Alzheimerۥs disease ( may be exacerbated )
3) Bleeding , gastrointestinal or rectal , undiagnosed
4) Bone fractures Aluminum hydroxide has the ability to form the insoluble complex of aluminum phosphate , which is excreted in the feces . This may lead to lowered serum phosphate concentrations and phosphorus mobilization from the bone .
5) Constipation or fecal impaction
6) Chronic diarrhea( possible increase danger of phosphate depletion with aluminum containing antacids )
7) Gastric outlet obstruction
10) Renal function impairment
11) Sensitivity to aluminium
Pregnancy : Antacide are generally considered safe as long as chronic high doses are avoided .
Breast feeding : problems in humans have not been documented; although some aluminum may be distributed into breast milk , the concentration is not great enough to produce an effect in the neonate .
pediatrices : Antacids should not be given to young children (up to 6 years of age ) unless prescribed by a physician . Since children are not usually able to describe their symptoms precisely , proper diagnosis should precede the use of an antacid .
Use of aluminum-containing antacids is contraindicated in very young children because there is a risk of aluminum toxicity,especially in dehydrated infants and children or infants and children with renal failure .
Geriatrics : Metabolic bone disease commonly seen in the elderly may be aggravated by the phosphorus depletion , hypercalciuria and inhibition of absorption of intestinal fluoride caused by the chronic use of aluminum containing antacids. Also , elderly patients are more likely to have age related renal function or impairment , which may lead to aluminum retention .
Although it is not known whether high intake of aluminum leads to Alzheimer’s disease , the use of aluminum – containing antacids in Alzheimer’s patients is not generally recommended .
- Acidifiers , urinary such as : Ammonium chloride , Ascorbic acid potassium or sodium phosphate , Racemethionine .
- Amphetamines or Quinidine
- Anticholinergics or other medications with anticholinergic activity .
- Digitalis glycosides
- Enteric coated medications such as bisacodyl
- Folic acid
- Histamine H2 – receptor antagonists
- Iron preparations ( oral )
- Izoniazide ( oral )
- Phosphate , (oral )
- Sodium fluoride
- Tetracycline ( oral )
Adverse reactions :
- – With long – term use in chronic renal failure in dialysis patients ( Neuorotoxicity )
- With large doses : fecal impaction , swelling of feet or lower legs .
- with long – term use : hypercalcemia associated with milk alkali syndrome , Osteomalacia and osteoporosis due to phosphat depletion,
- phosphorus depletion syndrome.
- Chalky taste
- stomach cramps
Dosage and administration :
For use in peptic ulcer :
In the treatment of peptic ulcer disease , to achieve adequate antacid effect in the stomach at the optimum time , most antacids are administered 1 and 3 hours after meats for prolonged acid-neutralizing effect and at bedtime .
In the treatment of peptic ulcer , 960 mg to 3.6 grams are given orally every one or two hours during waking hours , the dosage being adjusted as needed . For extremely severe symptoms of peptic ulcer ( hospitalized patients ) , 2.6 to 4.8 grams diluted with two to three parts of water may be given intragastrically every thirty minutes for periods of twelve or more hours a day .
For antihyper phosphatemic use :
1.9 to 4.8 grams of aluminum hydroxide are given orally three or four times a day in conjunction with dietary phosphate restriction . In children, a does of 50 to 150 mg/kg of body weight is given in four to six divided doses in conjunction with dietary phosphate restriction .
Store below 30° C . in a well-closed container . Protect from moisture .
USP DI 2004