Compare Mucinex D vs. Delsym

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Mucinex D
(Guaifenesin / Pseudoephedrine)


Breaks up mucus and relieves congestion. Mucinex D (Guaifenesin / Pseudoephedrine) is good if you have a stuffy nose and a cough with mucus, but it could keep you up at night.Relieves coughing. Delsym (Dextromethorphan) is a good option for treating dry cough. It's not safe to take with MAO inhibitors though.
How it works
Mucinex D (Guaifenesin / Pseudoephedrine) is a combination medicine. Guaifenesin (an expectorant) breaks up and thins out mucus. Pseudoephedrine (a decongestant) clears your sinuses.Delsym (Dextromethorphan) is a cough suppressant.
Type of medication
Cough suppressantOver-the-counter
Available as
  • Extended release
  • Pill
  • Liquid extended release
Used for (click to learn more)
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
5.155573376102646Mucinex D
Reviews for Mucinex D (Guaifenesin / Pseudoephedrine)
of people say Mucinex D (Guaifenesin / Pseudoephedrine) is worth it
say it works well
say it's a big hassle
Reviews for Delsym (Dextromethorphan)
12% vs. Mucinex D (Guaifenesin / Pseudoephedrine)
10% vs. Mucinex D (Guaifenesin / Pseudoephedrine)
5% vs. Mucinex D (Guaifenesin / Pseudoephedrine)
Side effects

We haven’t found good data for Mucinex D side effects.

FDA side effect reports for Mucinex D »

We haven’t found good data for Delsym side effects.

FDA side effect reports for Delsym »
Risk factors for serious side effects
  • History of high blood pressure
  • History of heart problems
  • Age 65 years or older
    Detailed Mucinex D (Guaifenesin / Pseudoephedrine) risks & warnings »
    • Using other medications that affect serotonin
    Detailed Delsym (Dextromethorphan) risks & warnings »
    Pregnancy category
    No specific alcohol-related info.No specific alcohol-related info.
    No specific food-related info.No specific food-related info.
    Kidneys and liver
    No specific kidneys and liver-related info.No specific kidneys and liver-related info.
    No specific sex-related info.No specific sex-related info.
    No specific sleep-related info.No specific sleep-related info.
    No specific weight-related info.No specific weight-related info.
    Upsides and benefits
    • Mucinex D (Guaifenesin / Pseudoephedrine) is a combination medicine that relieves multiple cold symptoms. It's good to use if you have sinus and chest congestion.
    • Helps loosen the mucus in your airways so that you can cough it up more easily.
    • Works well to clear nasal congestion and help you breathe better.
    • Good for treating dry cough.
    • Available in drugstores either by itself or in combination with other medications to treat cold and allergy symptoms.
    • Available as a liquid and a tablet.
    • Some products relieve cough for up to 12 hours.
    Downsides and risks
    • Pseudoephedrine, the decongestant in Mucinex D (Guaifenesin / Pseudoephedrine), can make your heart race or make you feel anxious and restless.
    • Doesn't work as well if you use it for more than 4 days at a time.
    • Although you don't need a prescription to get Mucinex D (Guaifenesin / Pseudoephedrine), you need to show a photo ID to buy it in the drugstore.
    • Mucinex D (Guaifenesin / Pseudoephedrine) isn’t useful if you have a dry cough.
    • Can't take dextromethorphan if you're taking MAO inhibitors (drugs used to treat Parkinson's disease, depression, and other emotional conditions). If taken together, they will cause dangerously high blood pressure levels.
    • If you're taking this in combination with other cold and allergy medications, you should read labels closely to make sure you're not accidentally taking too much of a single ingredient.
    Tips from our pharmacists for people taking the medication
    • Drink plenty of fluids while taking Mucinex D (Guaifenesin / Pseudoephedrine) because liquid helps break down mucus.
    • You need to show an ID to buy Mucinex D (Guaifenesin / Pseudoephedrine) in the drugstore because it contains pseudoephedrine.
    • Don't take Mucinex D (Guaifenesin / Pseudoephedrine) too close to bedtime since it can keep you awake.
    • Can cause an irregular or fast heartbeat, and can raise your blood pressure.
    • Follow age-specific dosing instructions on how much to take. Don't take more than the recommended dose.
    • Cough suppressant starts working in 15 to 30 minutes.
    • If your cough lasts more than 7 days, call your doctor.
    • Follow age-specific dosing instructions on how much to take. Don't take more than the recommended dose.
    Learn more
    More about Mucinex DSide effectsReviews & ratingsAlternativesFDA package insert
    More about DelsymSide effectsReviews & ratingsAlternativesFDA package insert