Aluminum Hydroxide/Magnesium Hydroxide/Simethicone

Aluminum hydroxide/magnesium hydroxide/simethicone is a combination medication used to relieve symptoms of acid indigestion, heartburn, sour stomach, upset stomach, and bloating.

The drug formulations contain varying compositions of the three components and are available over the counter (OTC). Aluminum hydroxide and magnesium hydroxide are antacids while simethicone is an antiflatulent drug that reduces abdominal gas and bloating.

Both aluminum hydroxide and magnesium hydroxide neutralize stomach acid, protecting the gastrointestinal (GI) lining. They bind to hydrochloric acid and eliminate it in the stools. Magnesium hydroxide acts rapidly in the stomach, while aluminum hydroxide sustains the effects.

Magnesium hydroxide also promotes bowel movement by drawing water into the colon. Aluminum hydroxide can cause constipation, but magnesium hydroxide’s laxative properties balance this effect. Additionally, aluminum hydroxide prevents the absorption of dietary phosphate, reducing phosphate levels in the blood. However, neither antacid affects stomach acid production.

Simethicone is a silicone compound that relieves gas symptoms. It changes the surface tension of gas bubbles, causing them to collapse and facilitating gas passage in the GI tract. However, simethicone does not prevent gas formation or treat conditions that increase gas production.

Warnings

• Do not use aluminum hydroxide/magnesium hydroxide/simethicone if you are hypersensitive to any component in the formulation.
• Do not take aluminum hydroxide/magnesium hydroxide/simethicone if you have kidney disease.
• Prolonged use may cause low blood phosphate levels (hypophosphatemia), leading to loss of appetite, weakness, and softening of bones (osteomalacia). Use with caution.
• Do not use the combo drug to treat hyperphosphatemia.
• Aluminum hydroxide/magnesium hydroxide/simethicone can cause high magnesium levels (hypermagnesemia) or aluminum intoxication, especially in patients with renal insufficiency. This may result in osteomalacia and dialysis encephalopathy, an aluminum-related brain damage.
• May change the rate of absorption of concurrently administered oral drugs.
• Some formulations may contain propylene glycol, which is toxic in large amounts.
• Some formulations may contain sodium and may not be suitable for people on restricted sodium diets.
• Some formulations may contain phenylalanine and should not be used in patients with phenylketonuria, an inherited condition with inability to break down phenylalanine.

Side Effects

Common side effects of aluminum hydroxide/magnesium hydroxide/simethicone include nausea, vomiting, chalky taste, stomach cramps, constipation, fecal impaction, hemorrhoids, rebound hyperacidity, aluminum intoxication, softening of bones (osteomalacia), milk-alkali syndrome (high calcium in blood, high alkalinity of tissues, kidney injury), abdominal pain, diarrhea, rectal bleeding, electrolyte imbalance, and high magnesium in blood (hypermagnesemia).

Contact your doctor immediately if you experience any of the following symptoms or serious side effects:

• Serious heart symptoms such as fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
• Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
• Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
• Serious eye symptoms like blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.

This is not a complete list of all side effects or adverse reactions. Call your doctor for medical advice about serious side effects or adverse reactions. Report side effects or health problems to the FDA at 1-800-FDA-1088.

Dosages

Liquid

• (200 mg/200 mg/20 mg)/5 mL
• (400 mg/400 mg/40 mg)/5 mL

Suspension

• (225 mg/200 mg/25 mg)/5 mL

Adult:

Dyspepsia, Abdominal Bloating

• 10-20 mL orally every 4-6 hours taken 1 hour before or 3 hours after meals, OR
• Chew 2-4 tablets every 4-6 hours; not to exceed 12 tablets/24 hours

Pediatric:

• Safety and efficacy not established

Overdose

• Overdose of aluminum hydroxide/magnesium hydroxide/simethicone combo is unlikely to cause serious side effects. Overdose may cause constipation or diarrhea, and the symptoms should resolve with discontinuation of the drug.
• Chronic use may cause aluminum toxicity and increased blood levels of magnesium.

Drug Interactions

Inform your doctor of all medications you are currently taking to check for possible interactions. Do not start, stop, or change the dosage of any medication without your doctor’s recommendation.

• Severe interactions of aluminum hydroxide/magnesium hydroxide/simethicone include pazopanib and raltegravir.

The listed drug interactions are not exhaustive. Visit the RxList Drug Interaction Checker for more information.

Always tell your doctor, pharmacist, or health care provider about all prescription and over-the-counter medications you use, including dosage. Keep a list of this information. Consult your doctor or health care provider for any questions about the medication.

Pregnancy and Breastfeeding

• Use aluminum hydroxide/magnesium hydroxide/simethicone during pregnancy only if maternal benefits outweigh potential risks to the fetus.
• Unknown presence of aluminum hydroxide/magnesium hydroxide/simethicone in breast milk. Use with caution if nursing.

General Information

• Take aluminum hydroxide/magnesium hydroxide/simethicone as directed on the label.
• Check with your doctor before taking OTC aluminum hydroxide/magnesium hydroxide/simethicone if you have a sodium or magnesium-restricted diet.
• Do not self-medicate for more than 14 days. If symptoms persist, discontinue the drug and consult your physician.
• Store safely out of reach of children.
• In case of overdose, seek medical help or contact Poison Control.

Summary

Aluminum hydroxide/magnesium hydroxide/simethicone is a combination medication used to relieve symptoms of acid indigestion, heartburn, sour stomach, upset stomach, and bloating. Side effects include nausea, vomiting, chalky taste, stomach cramps, constipation, abdominal pain, diarrhea, rectal bleeding, electrolyte imbalance, and high magnesium in the blood. Do not use long-term. Consult your doctor before taking if pregnant or breastfeeding.