Magnesium Hydroxide
Also known as: Milk of Magnesia, Magnalax, Carmilax, Polymag, Rumen Bolus, Instamag, Polyox, Laxade, Maalox, Phillips' Chewable
* Oral magnesium hydroxide products (like Milk of Magnesia) are available over-the-counter (OTC), but **do not give on a regular basis without veterinary supervision**. * May cause diarrhea. Ensure your pet has access to plenty of fresh water. * Separate this medication from other oral drugs by at least 2 hours to prevent absorption issues. * Contact your veterinarian if your pet becomes lethargic or if diarrhea persists.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Rumen overload syndrome
- Rumen overload syndrome
- Antacid
- Rumen overload syndrome (Adults)
- Rumen overload syndrome (Calves)
- Adjunctive gastroduodenal ulcer therapy in foals
- Adjunctive treatment of hypomagnesemia with GI disease and severe hypocalcemia
- Adjunctive therapy for gastric ulcers
- Antacid
How it is given
Possible side effects
- Diarrhea or frequent loose stools
- Hypermagnesemia (especially in patients with severe renal insufficiency)
- Constipation (if using combination products with aluminum)
- Hypophosphatemia (with chronic use of aluminum-containing products)
Cautions & contraindications
- Renal disease (due to risk of hypermagnesemia)
- Gastric outlet obstruction (for aluminum-containing products)
- Use cautiously in patients on sodium- or potassium-restricted diets (some products contain significant amounts)
- Magnesium-containing antacids are contraindicated in patients with renal disease. Oral magnesium hydroxide should only be used clinically in ruminants with documented rumen acidosis and should not be used for treatment of other suspected rumen disorders or hypomagnesemia. Chronic use may lead to electrolyte abnormalities.
Drug interactions
- Quinidine: Increased absorption or pharmacologic effect may occur
- Sodium Polystyrene Sulfonate: May decrease the potassium-lowering effectiveness; may cause metabolic alkalosis in renal failure patients
- Sustained-release medications: May alter absorption by changing GI transit times when used at laxative dosages
- Sympathomimetic agents: Increased absorption or pharmacologic effect may occur
- Fluoroquinolones: Decreased absorption (chelation); separate doses by at least 2 hours
- Tetracyclines: Decreased absorption (chelation); separate doses by at least 2 hours
- Azole Antifungals (Ketoconazole, Itraconazole): Decreased absorption due to increased gastric pH; separate doses by at least 2 hours
- Digoxin: Decreased absorption; separate doses by at least 2 hours
- Iron Salts: Decreased absorption; separate doses by at least 2 hours
- H-2 Antagonists: Decreased absorption; separate doses by at least 2 hours
Frequently asked questions
What is Magnesium Hydroxide used for in pets?
* Oral magnesium hydroxide products (like Milk of Magnesia) are available over-the-counter (OTC), but **do not give on a regular basis without veterinary supervision**. * May cause diarrhea. Ensure your pet has access to plenty of fresh water. * Separate this medication from other oral drugs by at least 2 hours to prevent absorption issues. * Contact your veterinarian if your pet becomes lethargic or if diarrhea persists.
Is Magnesium Hydroxide safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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