Please check your internet connection and try again.
# Aluminium Hydroxide
## Overview
Aluminium hydroxide is an inorganic salt used as an antacid. It acts by neutralizing gastric hydrochloric acid, forming aluminium chloride and water. It is non-absorbable and has a slow onset of action compared to other antacids.
## Primary Indications
* Symptomatic relief of hyperacidity (heartburn, dyspepsia).
* Adjunctive treatment of peptic ulcer disease and GERD.
* Hyperphosphatemia (in patients with chronic kidney disease).
## Adult Dosing
* **Antacid:** 500 mg to 1800 mg orally between meals and at bedtime (or PRN). Maximum dosage varies by product; refer to individual labeling.
* **Hyperphosphatemia:** 500 mg to 1800 mg orally 3–4 times daily with meals. Dosing is highly individualized based on serum phosphorus levels.
## Pediatric Dosing
* **Antacid:** Safety and efficacy not well established. Common off-label dosage: 50–150 mg/kg/day in divided doses.
* **Hyperphosphatemia:** 50–150 mg/kg/day in divided doses with meals, titrated to target serum phosphate. Consult specific pediatric institutional protocols for titration schedules.
## Dose Adjustments
* **Renal Impairment:** Use caution. Chronic use in patients with renal failure (CrCl <30 mL/min) can lead to aluminium toxicity (encephalopathy, osteomalacia) due to reduced renal clearance of absorbed aluminium.
## Contraindications
* Hypersensitivity to aluminium products.
* Severe abdominal pain of unknown origin (potential appendicitis or bowel obstruction).
* Chronic use in patients with severe renal impairment (unless specifically indicated for phosphate binding under close supervision).
## Adverse Effects
* **Gastrointestinal:** Constipation (very common; often balanced with magnesium-based antacids), intestinal obstruction (with high doses/long-term use).
* **Metabolic:** Hypophosphatemia (with chronic/excessive use), hyperaluminemia (in renal impairment).
## Key Drug Interactions
* **Absorption Inhibition:** Aluminium hydroxide significantly decreases the absorption of tetracyclines, fluoroquinolones, ketoconazole, iron salts, and bisphosphonates. Separate administration by at least 2–4 hours.
* **pH Alters:** May decrease the absorption of drugs requiring an acidic gastric environment (e.g., atazanavir, dasatinib).
## Monitoring
* **Hyperphosphatemia:** Serum phosphorus, calcium, and intact PTH levels.
* **Long-term use:** Monitor for constipation and signs of aluminium toxicity in patients with compromised renal function.
## Clinical Pearls
* Aluminium hydroxide is notorious for causing constipation; many commercial products combine it with magnesium hydroxide to counteract this effect.
* It should be taken 1–3 hours after meals for maximal acid-neutralizing effect, or with meals when used as a phosphate binder.
* Systemic absorption is minimal in healthy patients with normal renal function, but citrate ingestion can significantly enhance aluminium absorption and should be avoided in patients with renal impairment.
***
*Disclaimer: This information is for educational purposes. Clinical guidelines, local protocols, and individual patient factors must be considered. Always consult the most recent product monograph and verified prescribing references before administering any medication.*
