Adults usually take 10–20 mL up to four times daily—max 80 mL/day (regular) or 60 mL/day (Max strength).
Maalox is a liquid antacid that eases heartburn, acid indigestion, sour stomach, and gas. Most bottles contain aluminum hydroxide and magnesium hydroxide to neutralize acid, plus simethicone to break up gas. Getting the dose right matters for quick relief and to avoid side effects like diarrhea or constipation. This guide explains dose ranges by strength, timing with meals, how long to use it, and when to skip or call a doctor.
What Maalox Strength Do You Have?
Labels list the amount per 5 mL (one teaspoon). Regular strength commonly lists 200 mg aluminum hydroxide, 200 mg magnesium hydroxide, and 20 mg simethicone per 5 mL. Max strength often lists 400 mg / 400 mg / 40 mg per 5 mL. Shake well before each dose so the medicine is evenly mixed.
Typical Adult Dose And Daily Limits
For regular strength liquid, adults take 10–20 mL up to four times in a day. Don’t exceed 80 mL in 24 hours. For Max strength liquid, adults take 10–20 mL up to four times, with a lower daily cap of 60 mL. These ranges match common labels and standard references and are meant for short-term use only (up to 14 days) unless a clinician tells you otherwise. References include the U.S. drug label database and recognized dosing summaries (DailyMed Maalox label; aluminum/magnesium hydroxide dosing).
Quick Dose Snapshot (By Strength)
The table below condenses what most adults need to know for the common liquid products. Always follow your own package if it gives different directions for that brand.
| Product Strength (Per 5 mL) | Typical Single Dose | Max In 24 Hours |
|---|---|---|
| Regular: 200 mg Al(OH)3 / 200 mg Mg(OH)2 + 20 mg simethicone | 10–20 mL, up to 4×/day | 80 mL/day |
| Max Strength: 400 mg Al(OH)3 / 400 mg Mg(OH)2 + 40 mg simethicone | 10–20 mL, up to 4×/day | 60 mL/day |
| “Plus” Variants (with simethicone) | 10–20 mL, up to 4×/day | Follow label; often 60–80 mL/day |
How Much Maalox To Take Safely — Dosage By Use
Heartburn after a heavy meal often settles with one 10–20 mL dose. Reflux that lingers through the evening may need a second dose at bedtime. Gas with pressure and bloating sometimes improves when you pick a version that includes simethicone.
Timing With Food
Many labels advise taking it 20 minutes to 1 hour after meals and again at bedtime. That timing helps cover the post-meal acid surge and night symptoms. You can also take a dose when symptoms hit during the day. See the UK patient leaflet for a common schedule and clear language on when to take it (Maalox Plus PIL).
How Long To Use It
Short-term use is the idea. If you’re dosing daily for more than two weeks, or you’re needing higher amounts to get relief, reach out to a clinician. Persistent heartburn can signal reflux disease or another cause that needs a tailored plan.
Who Should Skip Or Check First
Some people shouldn’t take aluminum/magnesium antacids without medical advice. Skip it or ask first if any of these apply:
- Kidney disease or dialysis: Magnesium and aluminum can build up and cause harm.
- Severe dehydration or salt restriction: Some versions contain sodium.
- Pregnancy or nursing: Many clinicians allow short-term use, but get personalized advice.
- Age under 12 years: Follow pediatric advice and product-specific directions.
These cautions appear on official labels and trusted medical references (see the U.S. label warnings on kidney disease and drug interactions on DailyMed warnings).
Drug Interactions You Can Prevent With Spacing
Aluminum and magnesium bind many medicines in the gut and reduce how much you absorb. The fix is simple: separate the timing. Common pairs that need spacing include thyroid pills, iron, and several antibiotics. If you’re on long lists of meds, ask a pharmacist to map out a schedule that avoids clashes.
Why Spacing Matters
The metal ions in antacids attach to certain drugs and form complexes that don’t absorb well. That’s why labels and reference texts repeat the advice to keep doses apart. Thyroid hormone and many antibiotics are the big ones to watch.
Simple Spacing Rules That Work
Use these practical gaps unless your own doctor gives a different plan. The times below are drawn from drug-interaction monographs and clinical reviews.
| Medicine/Class | Examples | Keep Apart By |
|---|---|---|
| Thyroid hormone | Levothyroxine | ≥ 4 hours from any aluminum/magnesium antacid |
| Fluoroquinolone antibiotics | Ciprofloxacin, levofloxacin | Take the antibiotic 2 hours before or 6 hours after the antacid |
| Tetracycline antibiotics | Doxycycline, tetracycline | 2–4 hours apart (some guides: 2 hours before, 6 hours after) |
| Iron supplements | Ferrous sulfate/gluconate | About 2 hours apart from antacids |
| Bisphosphonates | Alendronate | Separate by at least 2 hours; follow the tablet’s strict empty-stomach rules |
For the science and timing details, see: levothyroxine interaction summaries (separate by ≥4 hours), tetracycline/quinolone chelation guidance (2–4 hours apart), and a review on metal-binding interactions (overview of cation-drug interactions).
Side Effects And How To Reduce Them
Common: Loose stools (from magnesium) or constipation (from aluminum). Nausea and a chalky taste can pop up after a dose.
Less common but serious: In people with poor kidney function, magnesium or aluminum can accumulate. Symptoms may include muscle weakness, fatigue, or confusion. That’s why kidney disease is a red-flag condition for this class.
Tips to ease side effects:
- Use the lowest dose that calms your symptoms.
- Switch to a version with simethicone if gas is the main issue.
- Keep doses within the daily cap for your strength.
- Don’t take it right before or right after other meds that need spacing.
Step-By-Step: How To Measure And Take It
- Check the strength. Look for the mg per 5 mL on the front label.
- Shake well. Ten seconds with a tight cap.
- Measure with a dose cup or oral syringe. Kitchen spoons are inaccurate.
- Start with 10 mL. If symptoms persist, 20 mL is allowed within the same dosing window.
- Space doses. Up to four times in 24 hours. Keep within the daily limit for your strength.
- Time it with meals or symptoms. 20–60 minutes after food and at bedtime, or as needed for breakthrough episodes.
Special Situations
Nighttime Reflux
Many people get relief from a 10–20 mL bedtime dose. Pair it with simple changes: earlier dinner, smaller portions, less late-night alcohol, and raising the head of the bed by a few inches.
Frequent Heartburn
If you need daily antacids for weeks, talk with a clinician about other options. Acid blockers (H2 blockers or PPIs) may be better for chronic symptoms. A clinician can also rule out conditions that mimic reflux.
Constipation From Aluminum Salts
Pick a product with more magnesium relative to aluminum, since magnesium tends to loosen stools. Add fiber and fluids during the day and go for a walk after meals.
When To Stop And Call A Doctor
- Chest pain with sweating, shortness of breath, or pain spreading to jaw or arm.
- Black stools, vomiting blood, or severe belly pain.
- Heartburn on most days for two weeks or more.
- Unplanned weight loss, trouble swallowing, or food sticking.
- New symptoms if you’re over 55.
Label Math: How Many Doses Per Bottle?
Most bottles list the volume in mL. To estimate dose count, divide the total volume by your usual dose. A 355 mL bottle at 10 mL per dose yields about 35 doses; at 20 mL per dose, about 17 doses. That quick math helps you plan refills and avoid running out when symptoms flare.
Practical Examples Of Safe Schedules
Occasional Heartburn After Dinner
Take 10–20 mL about 30–45 minutes after the meal. If bedtime symptoms return, take another 10–20 mL, staying under the daily cap.
Frequent Daytime Burping And Bloating
Pick a version with simethicone. Try 10–20 mL after lunch and again after dinner. Add a short walk and smaller portions to reduce air swallowing and pressure.
When You Also Take Thyroid Pills Or Iron
Schedule Maalox so it sits outside those windows: keep thyroid pills at least 4 hours away; keep iron at least 2 hours away. A pill-organizer app or a simple note on the fridge can help.
The Takeaway And A Safe-Use Checklist
Maalox can calm acid quickly when you match the dose to the bottle strength and space it from sensitive meds. Keep these points front and center:
- Regular strength: 10–20 mL up to 4×/day (max 80 mL/day).
- Max strength: 10–20 mL up to 4×/day (max 60 mL/day).
- Best timing: 20–60 minutes after meals and at bedtime.
- Use short term (about 2 weeks) unless your clinician says otherwise.
- Kidney disease, pregnancy, or many daily meds: get personalized advice first.
- Keep thyroid pills 4 hours away; keep iron and many antibiotics a few hours apart.
Sources And Method
Dose ranges and limits were verified against the U.S. drug label database and widely used dosing references. Timing with meals and interaction spacing draw on patient leaflets and professional interaction monographs. Representative sources include the official U.S. label entry for this antacid on DailyMed and the UK patient leaflet for a simethicone-containing variant on the electronic Medicines Compendium, along with dosing summaries at Drugs.com and interaction timing guidance in professional monographs.