Mucinex Vs. Mucinex D vs. Mucinex DM:​ What Is The Difference?

Mucinex Vs. Mucinex D vs. Mucinex DM:​  What Is The Difference?

Mucinex Package Title


Mucinex is a popular over the counter medication for cough and cold symptoms that comes in a variety of formulations. It can be difficult to discern the difference between all the products available to you. Read our article below as we explain the active ingredients in each product and what they are used for.



Active Ingredient:  Guaifenesin

Mucinex, the original product, contains one active ingredient, guaifenesin. Mucinex is used as an expectorant which helps to loosen and thin mucus as well as bronchial secretions.  This is turn helps the body to remove the secretions from both the upper and lower airways. It also can help alleviate chest congestion.  Mucinex has shown proven efficacy and is very commonly used when people are experiencing cold/flu like symptoms.

Mucinex DM

Mucinex DM

Active Ingredients: Guaifenesin, Dextromethorphan
Unlike the original Mucinex, Mucinex DM contains two active ingredients, guaifenesin and dextromethorphan. Guaifenesin, as mentioned above, helps to thin and loosen mucus. Dextromethorphan is a very commonly used cough suppressant and is also the active ingredient in Delsym.
It may seem counter-intuitive to use a cough suppressant while guaifenesin is being used to thin out your secretions. Dextromethorphan will not completely eliminate your cough so you will still be able to bring up and clear out mucus. It will however certainly reduce cough frequency which can help immensely when your throat is irritated and coughing causes pain.

Mucinex D

Mucinex D

Active Ingredients: Guaifenesin, Pseudoephedrine

Mucinex D contains two active ingredients, guaifenesin and pseudoephedrine. Psuedoephedrine is in this formulation is used as a nasal decongestant. It is very effective in reducing nasal inflammation, a stuffy nose and to clear the sinuses. It is particularly effective when being used to alleviate sinus pressure.

While Mucinex and Mucinex DM are available on the shelves over the counter, Mucinex D must be purchased behind the pharmacy counter due to the Combat Methamphetamine Epidemic Act, which restricts the sale of the product.

Final Words

​Now that we have discussed the difference in products, let's answer a question pharmacists often get asked: which product is right for you in a given situation?

In general, regular Mucinex is recommended if you are only experiencing symptoms of excess mucus such as throat/chest congestion. Mucinex DM is recommended if you have a continuous, irritating cough in addition to mucus. Mucinex D is a good choice if there is nasal congestion or sinus pressure.

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