Compare Mucinex vs. Delsym

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Mucinex (Guaifenesin)

Over-the-counter
Breaks up mucus that causes cough.

Mucinex (Guaifenesin) is a useful medicine for loosening congestion in your chest and throat, and it lasts longer than other guaifenesin products.

3.8/ 5 average rating with 902 reviewsforMucinex
Relieves coughing.

Delsym (Dextromethorphan) is a good option for treating dry cough. It's not safe to take with MAO inhibitors though.

3.3/ 5 average rating with 127 reviewsforDelsym
Upsides
  • Mucinex (Guaifenesin) reduces the thickness and amount of mucus in your throat and chest.
  • Lasts longer than some other products that contain guaifenesin, such as Robitussin, because it's an extended-release form.
  • It’s available at the drugstore either by itself or in combination with other medications to treat cold and flu symptoms.
  • Available in liquid and tablet forms.
  • Mucinex (Guaifenesin) is alcohol- and sugar-free.
  • 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
  • Mucinex (Guaifenesin) is more expensive than other medications that treat congestion.
  • You need to drink a lot of fluids while taking this medication or it won't work as well.
  • Mucinex (Guaifenesin) isn’t useful if you have a dry cough.
  • Can cause nausea, headache, and an upset stomach.
  • 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.
Used for
Dosage forms
  • Extended release
  • Liquid
  • Pill
  • Liquid extended release
No pricing information available
No pricing information available
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Reviews
902 reviews so far
78%
saidit'sworth it
47%
saiditworked well
7%
saidit'sa big hassle

Have you used Mucinex (Guaifenesin)?

Leave a review
127 reviews so far
63%
saidit'sworth it
32%
saiditworked well
12%
saidit'sa big hassle

Have you used Delsym (Dextromethorphan)?

Leave a review
Side effects
The Mucinex (Guaifenesin) FDA package insert doesn’t have numbers about how common side effects are.
The Delsym (Dextromethorphan) FDA package insert doesn’t have numbers about how common side effects are.
Risks and risk factors
  • Serotonin syndrome
    • Using other medications that affect serotonin
See more detailed risks and warnings