Robitussin (dextromethorphan and guaifenesin) and Mucinex (guaifenesin) are two popular over-the-counter (OTC) medications taken to relieve coughing caused by the common cold and other breathing conditions like the flu. They work differently in the body due to their active ingredients.
Robitussin contains dextromethorphan and guaifenesin as its active ingredients. Dextromethorphan works as an antitussive (cough suppressant). This works by reducing your urge to cough.
Mucinex contains guaifenesin as its active ingredient, which works as an expectorant by thinning and loosening the mucus in your lungs and throat. This makes it easier for you to cough up phlegm (sputum).
This article compares the similarities and differences between Robitussin and Mucinex.
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Robitussin vs. Mucinex: Product Types
Robitussin is a cough suppressant that contains two active ingredients: dextromethorphan and guafenesin. It is available over the counter (OTC) in various products, including:
- Robitussin ER (Extended Release) 12-hour Cough Relief
- Robitussin Maximum Strength
- Robitussin Cough + Chest Congestion
- Robitussin Long-Acting Cough Gels
- Children’s Robitussin Cough + Chest Congestion
Mucinex works as an expectorant. It thins and loosens the mucus in the lungs and throat to make it easier to cough up phlegm. Unlike Robitussin, Mucinex contains only one active ingredient: guaifenesin.
Mucinex comes in the following OTC products:
- Mucinex ER (extended release)
- Mucinex Fast-Max Severe Congestion and Cough
Typical Dosing for Robitussin and Mucinex Products
The table below compares the dosing requirements for Robitussin and Mucinex products.
| Typical Dosing for Robitussin Products | ||||||
|---|---|---|---|---|---|---|
| Robitussin ER | Robitussin Maximum Strength | Robitussin Cough + Chest Congestion | Children’s Robitussin Cough + Chest Congestion | Mucinex ER | Mucinex Fast Max | |
| Adults and Children 12 and up | Solution: Take 10 milliliters (mL) every 12 hours not to exceed 20 mL in 24 hours | Solution: Take 20 mL every 4 hours Capsules: Take 2 capsules every 4 hours | Solution: Take 20 mL every 4 hours | Solution: Take 20 mL every 4 hours | Tablet: Take 1-2 tablets every 12 hours do not exceed 4 tablets in 24 hours | Caplet: Take 2 caplets every 4 hours Solution: 20 mL every 4 hours as needed |
| Children 6-12 years of age | Solution: Take 5 mL every 12 hours not to exceed 10 mL in 24 hours | Do not use | Do not use | Solution: 10 mL every 4 hours | Do not use | Do not use |
| Children 4-6 years of age | Solution: Take 2.5 mL every 12 hours not to exceed 5 ml in 24 hours | Do not use | Do not use | Solution: 5 mL every 4 hours | Do not use | Do not use |
| Children under 4 years of age | Do not use | Do not use | Do not use | Do not use | Do not use | Do not use |
Which Is Better: Mucinex or Robitussin?
Robitussin and Mucinex are both effective at relieving cough and congestion symptoms. However, they will not treat the underlying cause of the cough.
When deciding between Robitussin and Mucinex, look at the active ingredients to see if they will effectively treat your symptoms.
Mucinex contains guaifenesin, an expectorant, which thins and loosens mucus. This is most helpful if you have a productive cough. A productive cough is one that brings up mucus. Mucinex thins and loosens the mucus to help push it upward and out.
Robitussin also contains the ingredient dextromethorphan, which is a cough suppressant. For this reason, Robitussin is better suited to treat a dry cough because it reduces coughing and helps you sleep at night. A dry cough does not produce or bring up mucus.
While taking Robitussin or Mucinex, drink plenty of water to stay hydrated. Fluids can help loosen mucus or phlegm in your lungs and clear up congestion.
Side Effects
Both Robitussin and Mucinex share similar side effects. They are:
- Dizziness
- Drowsiness
- Nauseaor vomiting
- Stomach pain
Side effects specific to dextromethorphan are:
- Nervousness
- Lightheadedness
- Restlessness
The active ingredient dextromethorphan can also cause hallucinations in those who take doses above what is recommended by the manufacturer. This can increase your risk for abuse and dependence.
Side effects specific to guaifenesin are:
- Headache
- Skin rash
Are Robitussin and Mucinex Safe for Pregnancy?
Robitussin and Mucinex are generally safe to use during pregnancy at standard OTC doses. However, both products should be taken only when the benefits outweigh the risks—that is, when they are absolutely necessary.
Make sure to read all of the ingredients, especially in combination cough and cold medication products. Some products may contain alcohol, which should be avoided during pregnancy.
Drug Interactions
Robitussin and Mucinex should be avoided with these medications:
- Disulfiram
- Solosec (secnidazole)
- Monoamine oxidase inhibitors (MAOIs), such as Emsam (selegiline) or Nardil (phenelzine)
Do not take dextromethorphan with (or after two weeks of stopping) antidepressant medications like MAOIs.
This can cause rapid changes in your blood pressure, restlessness, and diarrhea. Talk to your healthcare provider if you are pregnant or breastfeeding before taking these medications.
How to Choose the Right Medication
When deciding whether to choose Robitussin or Mucinex, you may consider several different factors, such as:
- Type of cough: Depending on what type of cough you have, you can make a choice based on the active ingredients listed on the product label and how the medication works for your specific needs.
- Medical history and current medications list: This plays a role in whether there will be a potential drug reaction or interaction with any other drugs you take.
- The cost and accessibility of these medications at your local pharmacy.
Mucinex D vs Mucinex DM: What’s the Difference?
Summary
Robitussin and Mucinex are two OTC medicines that can help relieve chest congestion.
These medicines have different active ingredients: Robitussin contains dextromethorphan, while Mucinex contains guaifenesin.
It is important to note that these medications target different symptoms, so choosing between them depends on personal preferences, associated symptoms, and medical history.
Before taking either medication, it's always a good idea to check with your healthcare provider or pharmacist, especially if you have concerns about how they may interact with other medications or if you're pregnant or breastfeeding.
The author would like to recognize and thank Chinonso Lloyd Paul for contributing to this article.
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