Usage
- Medical Conditions: Aluminium hydroxide is prescribed for the symptomatic relief of heartburn, acid indigestion, sour stomach, and upset stomach associated with these symptoms. It is also used to manage hyperphosphatemia in patients with chronic kidney disease. Topically, it can act as a skin protectant.
- Pharmacological Classification: Antacid, phosphate binder.
- Mechanism of Action: Aluminium hydroxide neutralizes hydrochloric acid in the stomach, raising gastric pH and inhibiting pepsin activity. It also binds phosphate in the GI tract, preventing its absorption. Topically, it forms a protective barrier on the skin.
Alternate Names
- Aluminum hydroxide (US spelling)
- Alu-Cap
- AlternaGEL
- Amphojel
How It Works
- Pharmacodynamics: Aluminium hydroxide increases gastric pH, reducing pepsin activity and providing relief from acid-related symptoms. It binds dietary phosphate, reducing its absorption and thus lowering serum phosphate levels.
- Pharmacokinetics: Orally administered aluminum hydroxide has limited absorption from the GI tract. The absorbed portion is primarily excreted by the kidneys. Most of the ingested aluminum hydroxide is eliminated in the feces as insoluble aluminum phosphate complexes.
- Mode of Action: Acts by chemical neutralization of gastric acid and by binding phosphate ions. No receptor binding, enzyme inhibition, or neurotransmitter modulation is involved.
- Elimination Pathways: Primarily eliminated through feces; a small absorbed portion is renally excreted.
Dosage
Standard Dosage
Adults:
- Antacid: 600-1200 mg (tablets) or 640 mg (oral suspension) 3-4 times daily, after meals and at bedtime, as needed. Maximum: 3840 mg/24 hours.
- Hyperphosphatemia: 600-1200 mg 3-4 times daily with meals.
Children:
- Antacid: 5-15 mL of oral suspension every 3-6 hours, or 1 and 3 hours after meals and at bedtime. (Safer alternatives are preferred.)
- Hyperphosphatemia: 50-150 mg/kg/day orally, divided every 4-6 hours. Titrate dose to maintain phosphorus within normal range.
Special Cases:
- Elderly Patients: Start with the lower end of the dosing range. Monitor for constipation and fecal impaction.
- Patients with Renal Impairment: Use with caution. Aluminum toxicity may occur. Dosage adjustments are needed. Monitor serum aluminum levels.
- Patients with Hepatic Dysfunction: No specific dosage adjustments.
- Patients with Comorbid Conditions: Monitor patients with heart failure, edema, or cirrhosis.
Clinical Use Cases
- Specific dosage recommendations for clinical use cases like intubation, surgical procedures, mechanical ventilation, ICU use, and emergency situations are not explicitly defined for aluminum hydroxide.
Dosage Adjustments
- Dose reductions are needed for patients with renal impairment.
- Monitor phosphate, calcium, and aluminum serum levels during long-term use, especially in patients with renal failure.
Side Effects
Common Side Effects:
- Constipation
- Nausea
- Chalky taste
Rare but Serious Side Effects:
- Aluminum toxicity (especially in renal impairment)
- Osteomalacia
- Hypophosphatemia
- Encephalopathy
- Seizures
Long-Term Effects:
Adverse Drug Reactions (ADR):
- Milk-alkali syndrome
- Fecal impaction
- Bowel obstruction
- Hypomagnesemia
Contraindications
- Known hypersensitivity to aluminum hydroxide
- Severe renal impairment
- Hypophosphatemia
- Bowel obstruction
Drug Interactions
- Aluminum hydroxide reduces the absorption of many medications, including tetracycline antibiotics, quinolone antibiotics (ciprofloxacin), digoxin, iron salts, levothyroxine, pazopanib, raltegravir, and others. Separate administration times as recommended.
- Antacids can affect the absorption of other drugs by altering gastric pH.
Pregnancy and Breastfeeding
- Pregnancy: Aluminum hydroxide is generally considered safe during pregnancy when used as directed. However, it is advisable to use it only when the benefits outweigh the potential risks.
- Breastfeeding: Aluminum hydroxide is considered compatible with breastfeeding. Monitor infants for constipation.
Drug Profile Summary
- Mechanism of Action: Neutralizes gastric acid and binds phosphate.
- Side Effects: Constipation, nausea, aluminum toxicity (rare).
- Contraindications: Hypersensitivity, severe renal impairment, hypophosphatemia.
- Drug Interactions: Reduces the absorption of many drugs.
- Pregnancy & Breastfeeding: Generally considered safe.
- Dosage: Varies by indication and patient factors. See dosage section for details.
- Monitoring Parameters: Phosphate, calcium, and aluminum levels (in renal patients).
Popular Combinations
- Magnesium hydroxide: Commonly combined to counteract the constipating effects of aluminum hydroxide.
Precautions
- General Precautions: Assess renal function before and during prolonged use.
- Specific Populations: Use cautiously in elderly patients and those with renal impairment.
- Pregnant Women: Use only when clearly needed.
- Breastfeeding Mothers: Monitor infant for constipation.
- Children & Elderly: Monitor closely for side effects.
- Lifestyle Considerations: No specific restrictions.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Aluminium Hydroxide?
A: See dosage section for detailed recommendations.
Q2: What are the common side effects?
A: Constipation, nausea, chalky taste.
Q3: How does aluminum hydroxide work as an antacid?
A: It chemically neutralizes stomach acid, raising gastric pH.
Q4: Can I take aluminum hydroxide if I have kidney disease?
A: Use with caution in renal impairment. Dosage adjustments and monitoring are necessary due to the risk of aluminum toxicity.
Q5: Does aluminum hydroxide interact with other medications?
A: Yes, it can interfere with the absorption of numerous drugs. Consult the drug interaction section for details.
Q6: Can pregnant or breastfeeding women use aluminum hydroxide?
A: Generally considered safe but should be used under medical supervision.
Q7: What should I do if my symptoms worsen or don’t improve?
A: Consult a healthcare professional.
Q8: What is the difference between aluminum hydroxide and magnesium hydroxide antacids?
A: Aluminum hydroxide is more constipating, while magnesium hydroxide can cause diarrhea. They are often combined to balance these effects.
Q9: How should aluminum hydroxide be administered?
A: Oral suspensions should be shaken well before use. Tablets should be chewed thoroughly before swallowing. Take with food.
Q10: Are there any long-term risks associated with aluminum hydroxide use?
A: Potential long-term risks include osteoporosis with chronic use, particularly at high doses. Regular monitoring is recommended.
