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Guaifenesin DM Coupon - Guaifenesin DM 100mg/10mg/5ml ml of syrup

guaifenesin dm

Generic Mucinex DM
Used for Cough

Mucinex DM (guaifenesin / dextromethorphan) is an over-the-counter medication that's used to relieve cough and loosen mucus. It has two active ingredients: guaifenesin (an expectorant that clears chest congestion) and dextromethorphan (a cough suppressant that relieves cough). The medication is available as tablets, dissolvable granules, and liquid that are taken by mouth, each with different dosages, directions, and age limits. Extended-release tablets are taken every 12 hours, while the other forms are usually taken every 4 hours. Most people have few to no side effects when used as directed, but it can sometimes cause stomach upset, dizziness, and drowsiness.

Reviewed by:Last reviewed on October 22, 2023
basics-icon

What is Mucinex DM (guaifenesin / dextromethorphan)?

What is Mucinex DM (guaifenesin / dextromethorphan) used for?

  • Short-term relief of coughs caused by minor throat or lung irritation (e.g., common cold)
  • Loosens and breaks up mucus in the airways (chest congestion)

How Mucinex DM (guaifenesin / dextromethorphan) works

Mucinex DM (guaifenesin / dextromethorphan) is a combination of two medications.

  • Guaifenesin is an expectorant. It loosens mucus in your airways by making it thinner. This makes it easier to cough out mucus and help clear chest congestion.
  • Dextromethorphan is an antitussive medication, which is another name for a cough suppressant. It works on the part of your brain that makes you cough (your cough reflex). Its actions on the brain make you cough less.
When does Mucinex DM (guaifenesin / dextromethorphan) start working?Time passed since treatment started:
MINUTES
Initial effect
HOURS
Full effect
DAYS
WEEKS
MONTHS

Drug facts

Common BrandsMucinex DM, Adult Tussin Cough and Congestion DM, Robitussin Cough and Chest Congestion DM
Drug ClassExpectorant / Antitussive
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityOver-the-counter
side-effects-icon

Side effects of Mucinex DM (guaifenesin / dextromethorphan)

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

  • Side effects aren't common. See Other Side Effects.

Less Common Side Effects

Possible guaifenesin side effects:

  • Nausea
  • Diarrhea
  • Dizziness
  • Headache

Possible dextromethorphan side effects:

  • Belly discomfort
  • Vomiting
  • Constipation
  • Drowsiness
  • Trouble breathing
  • Racing heart

Mucinex DM (guaifenesin / dextromethorphan) serious side effects

Contact your healthcare provider immediately if you experience any of the following.

  • Serotonin syndrome: fast heart rate, sweating, muscle stiffness or spasms, high fever, confusion
  • Accidentally taking too much (overdose): feeling "high," hallucinations, fast heartbeat, slow breathing, seizures

Source: DailyMed

The following Mucinex DM (guaifenesin / dextromethorphan) side effects have also been reported

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

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

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Pros and cons of Mucinex DM (guaifenesin / dextromethorphan)

Pros

  • Available as a tablet, oral liquid, and dissolvable granules
  • Available over the counter without a prescription
  • Sugar-free options available, so okay to use for people with high blood sugar
  • Works within 30 minutes to help lessen cough

Cons

  • Not meant to be used long-term
  • Might need to take multiple times a day to relieve symptoms
  • Many states require you to be over 18 to buy it because of risk of misuse
  • Can't cut or crush extended-release tablets
pharmacist-tips-icon

Pharmacist tips for Mucinex DM (guaifenesin / dextromethorphan)

pharmacist
  • Tell your provider if you have a long-lasting cough that's caused by cigarette smoke or bronchitis, a cough that's linked to a breathing problem (e.g., asthma, emphysema), or a cough with a lot of mucus. Mucinex DM (guaifenesin / dextromethorphan) might not be appropriate for these type of coughs.
  • Please talk with your provider if your cough gets worse, comes back after clearing up, or lasts more than a week. Also let them know if you also have rash, fever, or headache. These might be signs of a more serious medical condition that can't be treated with Mucinex DM (guaifenesin / dextromethorphan).
  • For the extended-release tablets: Swallow the tablets whole with a full glass of water. Don't crush, break, or chew the tablets since it can change how the medication works.
  • For the oral liquids, solutions, and syrups: Be sure to use the medication dose cup, spoon, or oral syringe that comes in the packaging to measure out your child's dose. Ask your pharmacy if you need extras. Don't use household spoons because they might not be accurate. Using household spoons might cause your child to take the wrong amount of Mucinex DM (guaifenesin / dextromethorphan).
  • For the dissolvable granules: Pour the entire contents of packet onto the tongue and swallow. Make sure you don't chew or crunch the granules because doing so can change how the medication tastes.
  • Don't give Mucinex DM (guaifenesin / dextromethorphan) to toddlers to take without speaking to a provider because the medication can cause serious side effects in young children. Some safer options include using a clean humidifier or cool mist vaporizer or giving your toddler ice chips or popsicles to suck on to soothe a sore throat.
  • Guaifenesin and dextromethorphan can be found in many over-the-counter medications, so make sure you read package labels carefully. Don't use multiple products with these ingredients. In particular, taking too much dextromethorphan can cause serious side effects, such as fast heartbeat, slow breathing, confusion, or seizures.
  • Keep Mucinex DM (guaifenesin / dextromethorphan) up and away and out of children's reach and sight. Always put medication away every time you use it. This prevents children from accidentally swallowing any medication that was left out. Call a Poison Center at 1-800-222-1222 right away if your child might’ve accidentally swallowed the medication, even if you aren't completely sure.
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Common questions about Mucinex DM (guaifenesin / dextromethorphan)

Though uncommon, it's possible for Mucinex DM (guaifenesin / dextromethorphan) to make you drowsy. Avoid drinking alcohol while you're take Mucinex DM (guaifenesin / dextromethorphan) because it can make you feel even drowsier, which can lead to accidental injuries. Don't drive a car or operate machinery until you know how this medication affects you.

You can take Mucinex DM (guaifenesin / dextromethorphan) during the day or at night. But because this medication can sometimes cause drowsiness and dizziness, make sure to avoid activities that require alertness until you find out how it affects you. In addition, the extended-release tablets last for about 12 hours, so you'll typically take it once during the day and once at night. But the other formulations (e.g., oral solution, oral granules) typically last only 4 hours, so you might need to take it multiple times throughout the day and night for symptom relief. Talk to your provider or pharmacist if you need help figuring out which formulation best fits your needs.

Different formulations of Mucinex DM (guaifenesin / dextromethorphan) have different directions, strengths, and dosage limits. Make sure you're taking this medication correctly by following the product instructions on the package. If you're not sure, ask your provider or pharmacist about how much medication you can take per day. For Mucinex DM (guaifenesin / dextromethorphan) extended-release, regular-strength tablets, people 12 years and older can take 1 or 2 tablets by mouth every 12 hours; don't take more than 4 tablets in a 24-hour period. For Mucinex DM (guaifenesin / dextromethorphan) extended-release, maximum-strength tablets, people 12 years and older can take 1 tablet by mouth every 12 hours; don't take more than 2 tablets in a 24-hour period.

You can take the extended-release tablets every 12 hours as needed for cough and chest congestion. For most other formulations (e.g., oral solution, oral granules), you can take the medication every 4 hours on an as-needed basis if you have cough or chest congestion. Make sure you follow the product instructions on the package or talk with your provider or pharmacist about how often you can use your medication.

The "DM" on Mucinex DM products stands for dextromethorphan, which is a cough suppressant. It works to lessen cough by blocking your cough reflex. Mucinex DM contains dextromethorphan and another ingredient called guaifenesin, which helps relieve cough. Note that Mucinex DM is different than Mucinex D. Mucinex D contains guaifenesin and pseudoephedrine, a decongestant that relieves stuffy nose.

Speak with your provider about the risks and benefits of taking Mucinex DM (guaifenesin / dextromethorphan) for your cough during pregnancy. Mucinex DM contains two ingredients, dextromethorphan and guaifenesin. Although some studies didn't find a link between using dextromethorphan and birth defects, there aren't many studies on the use of guaifenesin during pregnancy. To be safe, it's best to avoid taking Mucinex DM (guaifenesin / dextromethorphan) in your first trimester. Ask your provider or pharmacist about safe options to relieve your cough if you're pregnant.

You shouldn't take Mucinex DM (guaifenesin / dextromethorphan) with Nyquil. Most products under the brand Nyquil contain dextromethorphan, which is one of the active ingredients in Mucinex DM (guaifenesin / dextromethorphan). Taking too much dextromethorphan can lead to overdose symptoms, such as feeling "high," hallucinations, fast heartbeat, slow breathing, and seizures. Keep in mind that many over-the-counter cough, cold, and flu medications contain similar ingredients, and it's best to avoid taking medications with overlapping ingredients. Always check with your provider or pharmacist before taking multiple over-the-counter cough, cold, and flu medications to make sure they're safe for you to take together.

Yes, it's generally considered safe to take ibuprofen (Advil) or acetaminophen (Tylenol)) with Mucinex DM (guaifenesin / dextromethorphan). These medications contain different ingredients and relieve different symptoms of cold and flu. Ibuprofen (Advil) and acetaminophen (Tylenol) are used to relieve pain and fever. And Mucinex DM (guaifenesin / dextromethorphan) is used to soothe cough and chest congestion. Keep in mind that these pain relievers have risks as well. Ibuprofen (Advil) has heart risks and can cause kidney problems, and acetaminophen (Tylenol) has a risk for liver damage. Before taking over-the-counter cold or flu medications, speak with your provider to make sure it's safe for you to do so.

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Risks and warnings for Mucinex DM (guaifenesin / dextromethorphan)

Mucinex DM (guaifenesin / dextromethorphan) 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 of overdose and misuse

  • Risk factors: Taking with other similar medications

Mucinex DM (guaifenesin / dextromethorphan) contains two common ingredients that are found in many other over-the-counter products. Using more than one product with the same ingredients can lead to an accidental overdose that can be dangerous. In addition, some people might misuse dextromethorphan on purpose, which can lead to poisoning, especially if it's taken at high doses. This is why many retail stores require you to be over 18 years old to purchase products containing dextromethorphan.

Talk to your provider or pharmacist before you start Mucinex DM (guaifenesin / dextromethorphan) if you're not sure whether you're already taking a medication that has dextromethorphan or guaifenesin in it. To prevent an accidental overdose, carefully follow the product instructions on the package.

Call your Poison Control Center at 1-800-222-1222 right away if you or anyone else might’ve accidentally taken too much Mucinex DM (guaifenesin / dextromethorphan), even if you aren't completely sure. Also call the Poison Control Center or get medical help if you or someone else has trouble breathing, hallucinations, or changes in behavior after taking the medication because these can be signs that someone's taken too much.

Interactions with certain medications for Parkinson's disease and depression

Talk to your provider first before using Mucinex DM (guaifenesin / dextromethorphan) if you're taking or have recently taken medications for Parkinson's disease or depression known as monoamine oxidase inhibitors (MAOIs). These medications can interact with Mucinex DM (guaifenesin / dextromethorphan) and cause dangerously high blood pressure. This drug interaction can also lead to a rare, but serious side effect called serotonin syndrome. Ask your provider about other options to relieve your cough symptoms if you've taken these medications in the past two weeks.

Caution use in people with phenylketonuria (PKU) - dissolvable granules only

The dissolvable granule formulation of Mucinex DM (guaifenesin / dextromethorphan) contain phenylalanine, a sweetener that's often added to medications. Phenylalanine is harmless to most people. But it can be dangerous to people with an inherited medical condition called phenylketonuria (PKU). Avoid using the dissolvable granules if you or your child has a history of PKU. Consider using the oral solution or tablet, which don't contain phenylalanine. Talk to a provider if you're not sure which products contain phenylalanine and which products are safer options before using any over-the-counter products.

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Mucinex DM (guaifenesin / dextromethorphan) dosage

The average cost for 118 ml of 100mg/10mg/5ml of Mucinex DM (guaifenesin / dextromethorphan) is $4.28 with a free GoodRx coupon. This is 49.53% off the average retail price of $8.48.
capsuleCapsule
DosageQuantityPrice as low asPrice per unit
200mg/10mg30 capsules$5.65$0.19
ml of oral solutionMl of oral solution
DosageQuantityPrice as low asPrice per unit
200mg/10mg/5ml473 ml$11.73$0.02
200mg/20mg/10ml60 ml$3.36$0.06
400mg/20mg/20ml118 ml$4.67$0.04
200mg/20mg/20ml118 ml$4.85$0.04
ml of syrupMl of syrup
DosageQuantityPrice as low asPrice per unit
100mg/10mg/5ml118 ml$4.28$0.04
tabletTablet
DosageQuantityPrice as low asPrice per unit
400mg/20mg30 tablets$4.54$0.15
600mg/30mg20 tablets$9.15$0.46
1200mg/60mg20 tablets$8.33$0.42

Typical dosage for Mucinex DM (guaifenesin / dextromethorphan)

This medication is made by many different manufacturers in different formulations. These formulations can have different directions and strengths.

Follow the specific product instructions on the package or talk with your provider or pharmacist about how to take this medication correctly. Some examples are listed below:

Extended-release tablets

  • Regular strength (Mucinex DM and generic): Each tablet contains 600 mg of guaifenesin and 30 mg of dextromethorphan.

    • People 12 years and older: The typical dose is 1 or 2 tablets by mouth every 12 hours. Don't take more than 4 tablets in a 24-hour period.
    • Children under age 12: Don't use. Ask your child's provider for other options.
  • Maximum strength (Mucinex DM Maximum Strength and generic): Each tablet contains 1,200 mg of guaifenesin and 60 mg of dextromethorphan.

    • People 12 years and older: The typical dose is 1 tablet by mouth every 12 hours. Don't take more than 2 tablets in a 24-hour period.
    • Children under age 12: Don't use. Ask your child's provider for other options.

Oral liquids

  • Children’s Robitussin Cough and Chest Congestion DM: Each teaspoon (5 mL) contains 50 mg of guaifenesin and 5 mg of dextromethorphan. Don't take more than 6 doses in a 24-hour period.
    • People 12 years and older: The typical dose is 20 mL by mouth every 4 hours.
    • Children 6 to 12 years: The typical dose is 10 mL by mouth every 4 hours.
    • Children 4 to 6 years: The typical dose is 5 mL by mouth every 4 hours.
    • Children under age 4: Don't use. Ask your child's provider for other options.

Oral granules

  • Mucinex Children's Cough and Chest Congestion Mini-Melts: Each packet contains 100 mg of guaifenesin and 5 mg of dextromethorphan. Don't take more than 6 doses in a 24-hour period.
    • People 12 years and older: The typical dose is 2 to 4 packets by mouth every 4 hours.
    • Children 6 to 12 years: The typical dose is 1 to 2 packets by mouth every 4 hours.
    • Children 4 to 6 years: The typical dose is 1 packet by mouth every 4 hours.
    • Children under age 4: Don't use. Ask your child's provider for other options.
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Mucinex DM (guaifenesin / dextromethorphan) reviews

GoodRx has partnered with to provide reviews on the different aspects of Mucinex DM (guaifenesin / dextromethorphan).

Effectiveness

Learn more about the effectiveness of Mucinex DM (guaifenesin / dextromethorphan) based on real life experiences.

Overall Rating

Based on 2 people taking this medication

1.3

Effectiveness by condition:

fibromyalgia2 reviews

1.3

Side effects
Learn more about the side effects others have reported while taking Mucinex DM (guaifenesin / dextromethorphan).

Severity of side effects

Based on 19 people taking this medication

None

69%

Mild

32%

Moderate

0%

Severe

0%

0%

50%

100%

Top side effects

Based on 19 people taking this medication

Sleepiness

11%

Fatigue

6%

Nausea

6%

Restlessness (akathisia)

6%

Usage
Review why people stop taking this medication and how long they take it.

Reasons people stopped taking Mucinex DM (guaifenesin / dextromethorphan)

Based on 20 people who have taken this medication

Course of treatment ended

60%

Did not seem to work

15%

Doctor's advice

10%

Other

10%

Personal research

5%

How long people take Mucinex DM (guaifenesin / dextromethorphan)

Based on 27 people who have taken this medication

2 to <5 years

4%

5 to <10 years

30%

10+ years

67%

0%

50%

100%

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How much does Mucinex DM (guaifenesin / dextromethorphan) cost?

To access savings, use a GoodRx coupon and pay just a fraction of the retail price.
Mucinex DM (guaifenesin / dextromethorphan) (generic)
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$3.36

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Mucinex DM (guaifenesin / dextromethorphan) contraindications

Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Mucinex DM (guaifenesin / dextromethorphan) will not be safe for you to take.

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What are alternatives to Mucinex DM (guaifenesin / dextromethorphan)?

There are a number of medications that your doctor can prescribe in place of Mucinex DM (guaifenesin / dextromethorphan). Compare a few possible alternatives below.
Mucinex DM (guaifenesin / dextromethorphan)
Used for:
  • Short-term relief of coughs caused by minor throat or lung irritation (e.g., common cold)
  • Loosens and breaks up mucus in the airways (chest congestion)
$3.36Lowest GoodRx priceView prices
Used for:
  • Temporarily easily cough from throat or lung irritations
  • Loosens mucus so that its easier to cough up
$6.25Lowest GoodRx priceView prices
Used for:
  • Cough in people ages 10 years and older
$11.36Lowest GoodRx priceView prices
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References

Best studies we found

Albrecht, H. H., et al. (2017). Role of guaifenesin in the management of chronic bronchitis and upper respiratory tract infections. Multidisciplinary Respiratory Medicine.

Centers for Disease Control and Prevention. (2021). Sore throat.

Centers for Disease Control and Prevention. (2023). Put your medicines up and away and out of sight.

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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