How does mucinex work

When you need some help shaking that chest congestion, Mucinex and Mucinex DM are two over-the-counter drugs that might help. Which one do you reach for? Mucinex and Mucinex DM both contain the drug guaifenesin. This is an expectorant. It helps loosen mucus from your lungs so that your coughs are more productive.

A productive cough brings up the mucus that causes chest congestion. This helps you breathe better. It also makes it easier for you to get rid of germs that may be trapped in the mucus that you cough up. Mucinex DM contains an additional drug called dextromethorphan. This drug helps control your cough. It works by affecting signals in your brain that trigger your cough reflex. This lessens your coughing. Both Mucinex and Mucinex DM are available as tablets you take by mouth.

You can take one or two tablets of either drug every 12 hours. For either drug, you should not take more than four tablets in 24 hours.

The tablets should not be used in people younger than 12 years. Shop for Mucinex. Mucinex and Mucinex DM tablets also both come in maximum-strength versions. These medicines contain double the amount of active ingredients. You should take no more than one maximum-strength tablet every 12 hours. Do not take more than two tablets in 24 hours. Shop for Mucinex DM. The packaging for the regular-strength and maximum-strength products is similar. There is also a liquid version of Mucinex DM available, but only in the maximum-strength form.

Talk to your doctor or pharmacist to decide which form is right for you. Mucinex DM liquid is only for people 12 years or older.

Shop for liquid Mucinex DM. There are Mucinex liquid products that are made especially for children 4 to 11 years of age. Most people tolerate these medications very well.

However, at higher dosages, the likelihood of side effects from the drugs in Mucinex and Mucinex DM increases. The chart below lists examples of possible side effects of Mucinex and Mucinex DM. These drugs are called monoamine oxidase inhibitors, or MAOIs. Examples of these drugs include:.

The interaction between these drugs and Mucinex DM can cause a serious reaction known as serotonin syndrome. This reaction can be life threatening. Symptoms of serotonin syndrome include:. Keep reading: Serotonin syndrome symptoms, treatment, and more ». Also, dextromethorphan, one of the ingredients in Mucinex DM, is a commonly misused drug. You should drink plenty of water with this medication. This medication can typically be taken with or without food.

A typical adult dose of Mucinex is 1 to 2 mg tablets every 12 hours, or 1 maximum strength tablet mg every 12 hours. The package directions should be followed very closely when giving Mucinex to children since the dose will vary based on the child's age and weight as well as the preparation used. Mucinex should not be given to children under the age of 4 years. You should talk to your healthcare provider before taking this medication if you are pregnant or breastfeeding, have kidney or liver disease, or if your cough may be caused by illness other than an upper respiratory infection or allergies such as emphysema or COPD.

Guaifenesin is generally well tolerated and considered safe to use, but like all medication may cause side effects. The most common side effects associated with this medication are:. Less common side effects of this medication include but are not limited to:. You should discontinue this medication and seek emergency medical attention if you experience symptoms of a severe allergic reaction to this medication which could include:.

You should also contact your healthcare provider if your cough persists longer than 7 days or if it is accompanied by a fever that does not go away. Mucinex has little evidence to suggest that it has a strong effect to help you clear secretions. Some of the combinations listed above also are counter-intuitive.

For instance, Mucinex DM has a cough suppressant, when you should be trying to thin your secretions and get rid of the excess mucus by coughing. Caution should always be used when taking combinations of medications that may reduce the efficacy of the other medication. Staying properly hydrated with water is an important factor in helping to reduce the frequency of having thick secretions which are then difficult to cough up.

There are many other medications that can help, but they are typically reserved for chronic issues related to cystic fibrosis, chronic COPD, and other respiratory conditions. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.

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Updated November 14, Medline Plus website. Updated July 15, Guaifenesin Oral Route. PubMed Health website. Updated October 1,