Over-the-counterLower-cost generic available

Mucinex Dm

(Dextromethorphan / Guaifenesin)

  • Pill
  • Extended release
  • Liquid
Back to: Full Site NavigationSkip to: side effects sectionSkip to: What to expect sectionSkip to: Risks and warnings sectionSkip to: Tips from users and pharmacists

Breaks up mucus and relieves cough.

Skip Upsides & Downsides section. Skip to side effects section.
Over-the-counterLower-cost generic available

Our pharmacists’ bottom line

Mucinex Dm (Dextromethorphan / Guaifenesin) is okay for loosening congestion in your chest and throat, but it could prevent you from coughing the mucus up. It comes as an extended-release tablet and a short-acting liquid.

  • Mucinex Dm (Dextromethorphan / Guaifenesin) is a combination medicine that relieves multiple cold symptoms. It's good to use if you have chest congestion and a cough.
  • Helps loosen the mucus and phlegm that builds up in productive and wet coughs.
  • The extended release version of Mucinex DM lasts up to 12 hours.
  • Mucinex Dm (Dextromethorphan / Guaifenesin) isn’t useful if you have a dry cough without mucus or phlegm.
  • The two medications in this product could potentially work against each other. Guaifenesin makes mucus easier to cough up, while dextromethorphan (the "DM" in Mucinex Dm (Dextromethorphan / Guaifenesin)) stops you from coughing.
  • Can cause sleepiness, dizziness, and an upset stomach.

Save on your next Mucinex Dm (Dextromethorphan / Guaifenesin) prescription

Be sure you’re getting the lowest price for your medication, even if you have insurance.

Skip side effects sections. Skip to What to Expect and Pharmacists Tips section.

Side effects for Mucinex Dm (Dextromethorphan / Guaifenesin)

Filter group. All currently selected
Filter group. All currently selected

These are side effects of Mucinex Dm (Dextromethorphan / Guaifenesin) reported to the FDA by people taking it, and by doctors and pharmacists.

0 reports

What to expect when you take Mucinex Dm (Dextromethorphan / Guaifenesin)

Skip what to expect section. Skip to Risks & Warnings section.
Tips from our pharmacists
  • Cough suppressant starts working in 15 to 30 minutes.
  • Follow age-specific dosing instructions on how much to take. Don't take more than the recommended dose.
  • Drink plenty of fluids while taking Mucinex Dm (Dextromethorphan / Guaifenesin) because liquid helps break down mucus.
  • If your cough lasts more than 7 days, call your doctor.

Risks and Warnings for Mucinex Dm (Dextromethorphan / Guaifenesin)

Skip Risks and Warnings section. Skip to Tips section.
  • People taking Mucinex Dm (Dextromethorphan / Guaifenesin) have reported nausea and vomiting. This is very rare and usually not serious. If you develop a fever with the nausea and vomiting, then talk to your doctor right away.

Means that some groups have a high risk of experiencing this side effect

Tips from pharmacists and people taking Mucinex Dm (Dextromethorphan / Guaifenesin)

Final section. Do you want to return to drug navigation?
The FDA category for this medication is N. It is advised that you: Unknown
  • Last winter I had this problem where when I would lay down to sleep I would start coughing. I took this and 20 minutes later I laid down - no coughing. After a week or so the problem went away. Came back again later and this helped again.
    Age: 22
    Gender: Woman
    Duration taken: A couple weeks