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Milk of Magnesia Coupon - Milk of Magnesia 355ml of 1200mg/15ml bottle of oral suspension

Milk of Magnesia

Generic
Used for Constipation
Used for Constipation

Milk of Magnesia (magnesium hydroxide) is an over-the-counter saline laxative that's most often used to treat occasional constipation in adults and children. It helps your body have a bowel movement by pulling water into your gut. This medication can also help relieve indigestion and heartburn by neutralizing your stomach acid. It's a liquid that's taken by mouth, and side effects aren't common at recommended dosages.

Reviewed by:
reviewer
Kristianne Hannemann, PharmD
reviewer
Cydnee Ng, PharmD
Last reviewed on December 14, 2023
BasicsSide effectsPros & consPharmacist tipsFAQsWarningsDosageCostAlternativesLatest newsImagesReferencesPricesMedicare
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What is Milk of Magnesia (magnesium hydroxide)?

What is Milk of Magnesia (magnesium hydroxide) used for?

  • Occasional constipation

  • Heartburn

  • Sour stomach

  • Indigestion

How Milk of Magnesia (magnesium hydroxide) works

Milk of Magnesia (magnesium hydroxide) is a saline laxative. It works by drawing water into your gut. This raises the number of bowel movements you have and softens your stools, making them easier to pass.

Milk of Magnesia (magnesium hydroxide) also acts as an antacid. It neutralizes, or balances, the acid in your stomach. This helps relieve heartburn, sour stomach, and indigestion.

Are you looking for information on magnesium oxide or magnesium citrate instead?
When does Milk of Magnesia (magnesium hydroxide) start working?
Time passed since treatment started:
MINUTES
HOURS
DAYS
WEEKS
MONTHS
Initial effect
Full effect

Drug Facts

Common BrandsMilk of Magnesia
Drug ClassSaline laxative
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityOver-the-counter
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What are the side effects of Milk of Magnesia (magnesium hydroxide)?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.
  • Bloody diarrhea
  • Severe constipation

Source: DailyMed

The following side effects have also been reported

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • High magnesium level—confusion, drowsiness, facial flushing, redness, sweating, muscle weakness, fast or irregular heartbeat, trouble breathing

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

pros-and-cons

Pros and cons of Milk of Magnesia (magnesium hydroxide)

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Pros

Can work as soon as 30 minutes to relieve constipation

Can be used in children (minimum age depends on the product)

Available over the counter (OTC) and as a lower-cost generic

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Cons

Not meant for long-term use

Might not be safe in people with kidney problems

Need to take some other medications at a different time than Milk of Magnesia (magnesium hydroxide) to prevent drug interactions

pharmacist-tips

Pharmacist tips for Milk of Magnesia (magnesium hydroxide)

pharmacist

  • Check with your provider whether Milk of Magnesia (magnesium hydroxide) is safe for you to take if you have kidney problems, stomach pain, nausea, vomiting, or are on a low-magnesium diet.

    • Drink a full glass of water (8 oz) with each dose of Milk of Magnesia (magnesium hydroxide) that you take. This helps prevent dehydration.

      • Shake the Milk of Magnesia (magnesium hydroxide) bottle well before you measure out your dose. This makes sure the medication is mixed evenly throughout the solution.

        • Only use the measuring spoon or dosing cup that comes with the packaging, and ask the pharmacy if you need extras. Don't use household measuring spoons or cups to measure your dose; you might take the wrong amount of medication if you use household spoons since they might not be accurate.

          • Tell your provider or pharmacist about all the medications you're taking since Milk of Magnesia (magnesium hydroxide) can change the way some medications work. You might need to separate when you take Milk of Magnesia (magnesium hydroxide) from some of your other medications to prevent drug interactions.

            • Stop taking Milk of Magnesia (magnesium hydroxide) and tell your provider if you don't have a bowel movement after 6 hours of taking the medication. Also contact a provider if you need to use the medication for more than 1 week. These can be signs of a more serious problem that your provider needs to check out.

              • Keep Milk of Magnesia (magnesium hydroxide) out of reach of children. The medication comes in flavored liquids that children can easily take by accident. Call the Poison Control Center (1-800-222-1222) right away if your child accidentally took too much Milk of Magnesia (magnesium hydroxide).

                faqs

                Frequently asked questions about Milk of Magnesia (magnesium hydroxide)

                How long does Milk of Magnesia (magnesium hydroxide) take to work?
                It typically takes between 30 minutes and 6 hours for Milk of Magnesia (magnesium hydroxide) to produce a bowel movement and relieve constipation. Contact a provider if you don't have a bowel movement after 6 hours of taking the medication.
                What should you do if Milk of Magnesia (magnesium hydroxide) doesn't work?
                Contact your provider right away if you don't have a bowel movement within 6 hours after you take Milk of Magnesia (magnesium hydroxide). Additionally, stop taking the medication and call your provider if you've tried taking Milk of Magnesia (magnesium hydroxide) for 1 week and you're still having constipation problems. These could be signs of a more serious medical condition. Your provider can help guide you to a different treatment option that might work better for you.
                How often can you take Milk of Magnesia (magnesium hydroxide)?
                For occasional constipation, you can take Milk of Magnesia (magnesium hydroxide) once a day, preferably at bedtime. You also have the option to split it up into smaller doses throughout the day, as long as you don't go over the maximum recommended dose per day. Speak with your provider to learn more about what dosing schedule would work best for you.
                How much Milk of Magnesia (magnesium hydroxide) should I take?
                The dose that's recommended for you will depend on your age, the reason you're using Milk of Magnesia (magnesium hydroxide), and what specific formulation of the medication you're using. But always make sure you don't go over the maximum recommended dose per day. For occasional constipation, the maximum dose for people 12 years and older is 4,800 mg per day and the maximum dose for children 6 to 11 years old is 2,400 mg per day. Refer to the product label or ask your pharmacist if you aren't sure how much Milk of Magnesia (magnesium hydroxide) you should take.
                Can you take Milk of Magnesia (magnesium hydroxide) daily?
                No. Milk of Magnesia (magnesium hydroxide) isn't meant for long-term use. Contact your provider if you need to use Milk of Magnesia (magnesium hydroxide) or any other laxatives for more than 1 week. Having frequent constipation or constipation that isn't relieved can be a sign of a more serious problem.
                Can you take Milk of Magnesia (magnesium hydroxide) while pregnant?
                Before starting any medications for constipation during pregnancy, speak to your provider or pharmacist about whether you should take Milk of Magnesia (magnesium hydroxide) and what other options there are for you. There isn't enough information to know for sure whether this medication is safe to use during pregnancy. It's best to try to prevent or relieve constipation by first making sure you're eating enough fiber, drinking enough fluids, and getting enough exercise. Talk to your provider if these tips aren't enough to relieve your constipation.
                Is Milk of Magnesia (magnesium hydroxide) safe for kids?
                To help with occasional constipation, Milk of Magnesia (magnesium hydroxide) can be used in children over 6 years of age. And to help with heartburn or indigestion, Milk of Magnesia (magnesium hydroxide) can be used in children over 12 years old. Read the package label carefully to see whether your child can take the medication based on their age and what they need it for. If you're not sure, ask a provider or pharmacist about safe options to use to help relieve your child's constipation, heartburn, sour stomach, or indigestion.
                Is Milk of Magnesia (magnesium hydroxide) the same as magnesium citrate?
                Milk of Magnesia (magnesium hydroxide) and magnesium citrate are different forms of magnesium. Both medications are used to treat occasional constipation, but Milk of Magnesia (magnesium hydroxide) is also sometimes used to treat heartburn, sour stomach, and indigestion. Magnesium citrate is also found in many dietary supplements.
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                What are the risks and warnings for Milk of Magnesia (magnesium hydroxide)?

                Milk of Magnesia (magnesium hydroxide) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

                risk-warning

                Signs that your intestinal problems might be more serious

                Stop taking Milk of Magnesia (magnesium hydroxide) and call your provider if you have rectal bleeding (blood that comes from your anus), stomach pain, nausea, or vomiting. Also contact your provider if you can't have a bowel movement within 6 hours after you take Milk of Magnesia (magnesium hydroxide). Let your provider know if you notice a sudden change in bowel habits over the last 2 weeks or if you've already used a laxative for more than 1 week without improvement. These could all be signs of a more serious problem that needs to be checked out by a provider.

                risk-warning

                Possible electrolyte changes

                • Risk factors: Kidney problems | Magnesium-restricted diet

                  Milk of Magnesia (magnesium hydroxide) might not be safe in people who have kidney problems since the medication can cause an electrolyte imbalance and lead to serious side effects. Talk to your provider before you use Milk of Magnesia (magnesium hydroxide) if you have kidney problems. Your provider can discuss whether you need to limit how much magnesium you get from your diet to avoid having electrolyte imbalances.

                  dosage

                  Milk of Magnesia (magnesium hydroxide) dosage forms

                  The average cost for 1 bottle of 355ml of 1200mg/15ml of Milk of Magnesia (magnesium hydroxide) is $4.31 with a free GoodRx coupon. This is 47.37% off the average retail price of $8.18.
                  bottle of oral suspension
                  Bottle of oral suspension
                  DosageQuantityPrice as low asPrice per unit
                  355ml of 1200mg/15ml1 bottle$4.31$4.31

                  Typical dosing for Milk of Magnesia (magnesium hydroxide)

                  Some Milk of Magnesia (magnesium hydroxide) products can be used for constipation only, and others for indigestion and heartburn only. The products can also have different strengths of magnesium hydroxide, which means that they can have different directions.

                  Make sure to read the package label carefully for instructions on how to take each specific Milk of Magnesia (magnesium hydroxide) product. Dosages of some example products are listed below.

                  Constipation

                  • Each 15 mL of medication contains 1,200 mg of magnesium hydroxide.

                  • Adults and children aged 12 years and older: The typical dose is 30 mL to 60 mL by mouth per day. The dose can be taken all at once at bedtime or split into smaller doses throughout the day.

                  • Children aged 6 to 11 years: The typical dose is 15 mL to 30 mL by mouth per day. The dose can be taken all at once at bedtime or split into smaller doses throughout the day.

                  • Children aged 5 years and younger: Ask your child's provider.

                  Heartburn, sour stomach, or indigestion

                  • Each 5 mL of medication contains 400 mg of magnesium hydroxide.

                  • Adults and children 12 years and older: The typical dose is 5 mL to 15 mL by mouth with a little water.

                  • Children aged 11 years and younger: Ask your child's provider.

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                  How much does Milk of Magnesia (magnesium hydroxide) cost?

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                  alternatives

                  What are alternatives to Milk of Magnesia (magnesium hydroxide)?

                  There are a number of medications that your doctor can prescribe in place of Milk of Magnesia (magnesium hydroxide). Compare a few possible alternatives below.
                  Milk of Magnesia (magnesium hydroxide)
                  Used for:

                  • Occasional constipation

                  • Heartburn

                  • Sour stomach

                  • Indigestion

                  $4.31 Lowest GoodRx priceView Prices
                  Magnesium citrate
                  Used for:

                  • Occasional constipation

                  $3.74 Lowest GoodRx priceView Prices
                  Polyethylene glycol (Miralax)
                  Used for:
                  $14.08 Lowest GoodRx priceView Prices
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                  Milk of Magnesia (magnesium hydroxide) images

                  This medicine is Colorless Bottle Of Oral Suspension.
                  This medicine is Colorless Bottle Of Oral Suspension.
                  This medicine is Colorless Bottle Of Oral Suspension.

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                  References

                  Best studies we found

                  Bashir, A., et al. (2024). Laxatives. StatPearls.

                  MedlinePlus. (2019). Magnesium Hydroxide.

                  PAI Holdings, LLC. (2022). Milk of magnesia- magnesium hydroxide suspension [package insert]. DailyMed.

                  View All References (3)

                  Rugby Laboratories. (2023). Milk of magnesia- magnesium hydroxide liquid [package insert]. DailyMed.

                  Salisbury, B. H., et al. (2023). Antiacids. StatPearls.

                  Schiller, L. R., et al. (2002). The therapy of constipation. Alimentary Pharmacology and Therapeutics.

                  GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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