aluminium hydroxide

Action and Spectrum

Actions: 

Aluminium-containing antacids act by neutralizing excess gastric hydrochloric acid, thereby increasing the pH of the stomach contents. This action provides symptomatic relief from conditions such as heartburn, acid indigestion, and gastric discomfort. In addition to their acid-neutralizing effects, aluminium salts can bind phosphate in the gastrointestinal tract, making them useful in reducing elevated phosphate levels in patients with chronic kidney disease. 

Spectrum: 

Their spectrum of use is limited to acid-related gastrointestinal symptoms and phosphate binding, and they do not have antimicrobial or systemic therapeutic effects. 

Drug Interaction

Adverse Reaction

Frequency not defined 

Osteomalacia 

Vomiting 

Nausea 

Stomach cramps 

Constipation 

Chalky taste 

Black Box Warning

None 

Contraindication / Caution

Contraindication 

Hypersensitivity 

Caution 

Aluminium toxicity 

Renal impairment 

Hypophosphatemia 

Pregnancy / Lactation

Pregnancy consideration:  

Category:  

Breastfeeding warnings: No data reported 

Pregnancy category: 

• Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 

• Category B: There is no affirmation of risk to the fetus found in animal reproduction studies, and there are not enough studies on pregnant women. 

• Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for a product in humans; Pregnant women must take care of the potential risks. 

• Category D: There is adequate data available with sufficient evidence of human fetal risk from various platforms. However, despite potential dangers may be used only in emergency cases for potential benefits. 

• Category X: Drugs listed in this category outweigh risks over benefits. The drug is not for pregnant women. 

• Category N: No data is available for the drug under this category. 

Pharmacology

Pharmacology: 

Aluminium-containing antacids, such as aluminium hydroxide, act by neutralizing gastric acid through a chemical reaction that forms water and aluminium salts. This leads to an increase in gastric pH, providing relief from acid-related symptoms. Aluminium salts react slowly with hydrochloric acid in the stomach, producing a sustained buffering effect.  

Pharmacokinetics: 

Absorption 

About 17% to 30% of the aluminium chloride that is formed is absorbed by the body. 

Metabolism 

It is not metabolized in the body. 

Excretion and Elimination 

Excretion occurs primarily through the urine for the small amount of aluminium that is absorbed, typically around 0.1 to 0.5 mg from standard daily doses of aluminium-containing antacids. Most of the aluminium, present as insoluble and poorly absorbed salts such as hydroxides, carbonates, phosphates, and fatty acid complexes, is eliminated through the feces. 

Adminstartion

Aluminium-containing antacids are administered orally, typically taken between meals and at bedtime for optimal effect. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: aluminium hydroxide 

Pronounced: a-LOO-mi-num hye-DROX-ide 

Why do we use aluminium hydroxide? 

Aluminium-containing antacids are used to relieve symptoms of excess stomach acid, such as heartburn, sour stomach, acid indigestion, and upset stomach. They are also used to manage conditions like gastroesophageal reflux disease (GERD) and peptic ulcer disease. Additionally, aluminium hydroxide may be used in the treatment of hyperphosphatemia in patients with chronic kidney disease, as it binds dietary phosphate in the gastrointestinal tract, reducing phosphate absorption.