Usage
Magaldrate + Simethicone is prescribed for the symptomatic relief of gastrointestinal discomfort caused by excess acid and gas. This includes heartburn, acid indigestion, sour stomach, dyspepsia, and symptoms associated with peptic ulcers, gastritis, esophagitis, gastroesophageal reflux disease (GERD), hiatal hernia, and flatulence.
This combination drug falls under the pharmacological classifications of antacid and anti-flatulent.
Mechanism of Action: Magaldrate, an aluminum-magnesium hydroxide complex, neutralizes gastric acid, raising the pH of the stomach and reducing pepsin activity. Simethicone, a surface-active agent, reduces the surface tension of gas bubbles, facilitating their coalescence and easier passage.
Alternate Names
While “Magaldrate + Simethicone” is the generic name, various brand names exist internationally and regionally. Some popular brand names include Riopan, Maalox Plus, Marlox Plus, and Maganta Plus.
How It Works
Pharmacodynamics: Magaldrate effectively neutralizes gastric acid without significantly altering stomach pH above the normal range (5-6). This reduces acid-related irritation and discomfort. Simethicone alters the physics of gas bubbles, promoting their combination and elimination through belching or flatus. It doesn’t prevent gas formation but facilitates its expulsion.
Pharmacokinetics: Magaldrate is minimally absorbed systemically, acting locally in the gastrointestinal tract. Simethicone is also not absorbed, passing through the digestive system unchanged. Elimination primarily occurs through fecal excretion for both components. The unabsorbed portion of magaldrate may be eliminated via renal pathways.
Mode of Action/Receptor Binding/Enzyme Inhibition/Neurotransmitter Modulation: Magaldrate’s mode of action is a straightforward chemical neutralization of gastric acid (HCl) to form water and aluminum and magnesium chloride salts. Simethicone acts physically by reducing surface tension without involving receptors, enzymes, or neurotransmitters.
Elimination pathways: Both drugs are eliminated primarily through fecal excretion.
Dosage
Standard Dosage
Adults: The typical adult dose is 5-10 mL of oral suspension or 1-4 chewable tablets, taken 20 to 60 minutes after meals and at bedtime, or as needed. The maximum daily dose should not exceed 80 mL of suspension (equivalent to 16 teaspoonfuls).
Children: Dosage for children under 12 should be determined and supervised by a physician. Dosing is generally based on weight:
- Under 10.9 kg: 20 mg of simethicone orally after meals and at bedtime as needed, not to exceed 240 mg/day.
- Over 10.9 kg: 40 mg of simethicone orally after meals and at bedtime as needed, not to exceed 480 mg/day.
Special Cases:
- Elderly Patients: Standard adult dosages are usually appropriate, but monitor closely for constipation and potential electrolyte imbalances. Dose adjustments may be necessary depending on renal function.
- Patients with Renal Impairment: Use with caution. Reduce dosage as necessary. Accumulation of magnesium and aluminum can occur with impaired renal function.
- Patients with Hepatic Dysfunction: No specific dosage adjustments are typically needed.
Clinical Use Cases
The dosage for Magaldrate + Simethicone doesn’t typically change in clinical settings such as intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations. It continues to be used for symptomatic relief of gastrointestinal distress related to excess acid and gas.
Dosage Adjustments
Dose adjustments primarily involve renal impairment, with reduced dosages necessary to prevent the accumulation of magnesium and aluminum.
Side Effects
Common Side Effects
Constipation, diarrhea, chalky taste, nausea, vomiting, stomach cramps, and loss of appetite.
Rare but Serious Side Effects
Aluminum toxicity (in patients with renal impairment), hypermagnesemia (high blood magnesium), hypophosphatemia (low blood phosphate), osteomalacia (bone softening), and metabolic alkalosis (in patients with renal impairment).
Long-Term Effects
Potential long-term effects with chronic use or overuse can include osteomalacia and electrolyte imbalances.
Adverse Drug Reactions (ADR)
Severe allergic reactions (rare).
Contraindications
Hypersensitivity to magaldrate or simethicone, severe renal impairment, hypophosphatemia, bowel obstruction, and appendicitis.
Drug Interactions
Magaldrate can affect the absorption of several medications, including tetracycline antibiotics, quinolone antibiotics, thyroid hormones (levothyroxine), iron supplements, bisphosphonates, digoxin, chloroquine, penicillamine, and some antihypertensives. It may also interact with other antacids. Consult a doctor before co-administering with other medications. Concurrent use with sodium polystyrene sulfonate or phosphate supplements should be avoided.
Pregnancy and Breastfeeding
Pregnancy Safety: Category C. Use with caution during pregnancy only if clearly needed, and under the supervision of a physician. The potential benefits should outweigh the potential risks.
Breastfeeding: Exercise caution. It is unknown if magaldrate is excreted in breast milk. Consult a physician.
Drug Profile Summary
- Mechanism of Action: Magaldrate neutralizes gastric acid; simethicone reduces the surface tension of gas bubbles.
- Side Effects: Constipation, diarrhea, chalky taste, nausea, vomiting. Rarely: aluminum toxicity, hypermagnesemia.
- Contraindications: Hypersensitivity, severe renal impairment, bowel obstruction.
- Drug Interactions: Numerous drug interactions; consult a doctor before co-administration.
- Pregnancy & Breastfeeding: Use with caution if benefits outweigh risks.
- Dosage: Adults: 5-10 mL or 1-4 tablets after meals and at bedtime. Pediatric use: consult physician.
- Monitoring Parameters: Renal function, magnesium levels (in long-term use or renal impairment), phosphate levels.
Popular Combinations
Magaldrate and simethicone are sometimes combined with domperidone (a prokinetic agent) or oxetacaine (a topical anesthetic). This enhances the relief of symptoms like nausea, vomiting, and upper abdominal pain associated with gastrointestinal disorders.
Precautions
- General Precautions: Screen for allergies, renal impairment, electrolyte imbalances.
- Specific Populations: Monitor renal function in elderly and renally impaired patients. Caution in pregnancy and breastfeeding. Consult a doctor before administering to children under 12.
- Lifestyle Considerations: Avoid alcohol, smoking, and large meals, which can exacerbate gastrointestinal symptoms.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Magaldrate + Simethicone?
A: Adults: 5-10 mL of suspension or 1-4 chewable tablets after meals and at bedtime, or as directed by a physician. Pediatric use: consult a physician, as dosing is weight-based.
Q2: How does Magaldrate + Simethicone work?
A: Magaldrate neutralizes stomach acid, while simethicone reduces the surface tension of gas bubbles, making it easier for them to be eliminated.
Q3: What are the common side effects?
A: Common side effects include constipation, diarrhea, chalky taste, nausea, and stomach discomfort.
Q4: Are there any serious side effects?
A: Rare but serious side effects can include aluminum toxicity, hypermagnesemia, and hypophosphatemia, especially in patients with kidney problems.
Q5: Can pregnant or breastfeeding women take this medicine?
A: Pregnant women should use it cautiously and only if clearly needed. Consult a doctor during pregnancy and breastfeeding.
Q6: Does this medication interact with other drugs?
A: Yes, it can interact with numerous medications, including certain antibiotics, thyroid medications, and heart medications. Always inform your doctor about all other medicines you are taking.
Q7: What conditions should I avoid this medicine with?
A: Avoid this medicine if you have severe kidney disease, bowel obstruction, appendicitis, or an allergy to its components.
Q8: What precautions should I take while using Magaldrate + Simethicone?
A: Inform your doctor about any pre-existing conditions. Avoid alcohol, smoking, and trigger foods. Monitor for persistent side effects. Consult your doctor about long-term use.
Q9: Can I take this medicine if I have a low-magnesium diet?
A: Consult your doctor first, as it can impact magnesium levels.
Q10: Can I take this medicine along with other antacids?
A: It’s best to avoid concurrent use of other antacids, especially those containing aluminum or magnesium, to prevent adverse effects or drug interactions. Always check with your physician.
