Head-to-head comparisons of medication uses, side effects, warnings, and more.
Mucinex DM (guaifenesin/dextromethorphan) and Deconex DMX (dextromethorphan/guaifenesin/phenylephrine) are both over-the-counter medications used to relieve cough and congestion, but they have some differences. Mucinex DM combines an expectorant (guaifenesin) to thin mucus and a cough suppressant (dextromethorphan) to reduce your urge to cough. It’s available in many different forms, each with different dosages, directions, and age limits. Mucinex DM is taken every 4 to 12 hours, depending on the formulation. Deconex DMX has the same ingredients as Mucinex DM, as well as a decongestant (phenylephrine) to help relieve nasal congestion. Deconex DMX needs to be taken more frequently, every 4 to 6 hours. Neither medication should be taken in children less than 4 years old. Mucinex DM is generally better tolerated with fewer common side effects, whereas Deconex DMX can cause dizziness, sleepiness, and headache.
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Deconex DMX is a combination of three medications: dextromethorphan (a cough suppressant), guaifenesin (an expectorant), and phenylephrine (a decongestant). It's used for cough and congestion and available over-the-counter as tablets and a liquid.
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.
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