Mucinex DM

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Mucinex DM – Uses, Side Effects, and More

This combination medication is used to relieve coughs caused by the common cold, bronchitis, and other breathing illnesses. Guaifenesin belongs to a class of drugs known as expectorants. It works by thinning and loosening mucus in the airways, clearing congestion, and making breathing easier. Dextromethorphan belongs to a class of drugs known as cough suppressants. It acts on a part of the brain (cough center) to reduce the urge to cough.If you are self-treating with this medication, it is important to read the package instructions carefully before you start using this product to be sure it is right for you. (See also Precautions section.)Cough-and-cold products have not been shown to be safe or effective in children younger than 6 years. This product (sustained-release) is not recommended for use in children younger than 12 years unless specifically directed by the doctor. Ask your doctor or pharmacist for more details about using your product safely.These products do not cure or shorten the length of the common cold and may cause serious side effects. To decrease the risk for serious side effects, carefully follow all dosage directions. Do not use this product to make a child sleepy. Do not give other cough-and-cold medication that might contain the same or similar ingredients (see also Drug Interactions section). Ask the doctor or pharmacist about other ways to relieve cough and cold symptoms (such as drinking enough fluids, using a humidifier or saline nose drops/spray).

How to use Mucinex DM

Take this medication by mouth with or without food, as directed by your doctor, usually every 12 hours with a full glass of water. If you are self-treating, follow all directions on the product package. If you have any questions, ask your doctor or pharmacist.

Dosage is based on your age, medical condition, and response to treatment. Do not take more than 2 doses in 24 hours. Do not increase your dose or take this drug more often than directed.

Do not crush or chew this medication. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.

Drink plenty of fluids while taking this medication. Fluids will help to break up mucus and clear congestion.

Improper use of this medication (abuse) may result in serious harm (such as brain damage, seizure, death). Do not increase your dose, take it more frequently, or use it for a longer time than directed.

Tell your doctor if your cough returns, or if it is accompanied by headache that doesn’t go away, fever, severe sore throat, rash, or if it lasts or gets worse after 7 days. These may be signs of a serious medical problem. Get medical help right away if you think you may have a serious medical problem.

Mucinex DM

Generic name: dextromethorphan and guaifenesin [ DEX-troe-me-THOR-fan-and-gwye-FEN-e-sin ]
Brand names: Aquatab DM, Broncotron, Coricidin HBP Chest Congestion & Cough, DayQuil Mucus Control DM, Delsym Cough Plus Chest Congestion DM, . show all 15 brands Fenesin DM IR, G-Zyncof, Mucinex DM, Phlemex, Robitussin Cough + Chest Congestion DM, Safetussin DM, Siltussin DM, TabTussin DM, Tussin DM, Zyncof
Drug class: Upper respiratory combinations

Medically reviewed by Drugs.com on Oct 24, 2022. Written by Cerner Multum.

What is Mucinex DM?

Dextromethorphan is a cough suppressant. Guaifenesin is an expectorant.

Mucinex DM is a combination medicine used to treat cough and chest congestion caused by the common cold or allergies.

Dextromethorphan will not treat a cough that is caused by smoking.

There are many brands and forms of this medication available and not all brands are listed on this leaflet.

Mucinex DM may also be used for purposes not listed in this medication guide.

Warnings

Do not use Mucinex DM if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

Before taking this medicine

Do not use this medicine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, and tranylcypromine.

Ask a doctor or pharmacist if this medicine is safe to use if you have:

• a cough with mucus; or
• asthma, emphysema, or chronic bronchitis.

Ask a doctor before using this medicine if you are pregnant or breast-feeding.

This medicine may contain phenylalanine. Check the medication label if you have phenylketonuria (PKU).

How should I take Mucinex DM?

Use exactly as directed on the label, or as prescribed by your doctor. Cold or cough medicine is only for short-term use until your symptoms clear up.

Always follow directions on the medicine label about giving cough or cold medicine to a child. Do not use the medicine only to make a child sleepy. Death can occur from the misuse of cough or cold medicines in very young children.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You may need to shake the liquid before you measure a dose. Follow all directions on the label.

Swallow the extended-release tablet whole and do not crush, chew, or break it.

Sprinkle the granules directly onto your tongue and swallow right away.

Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking Mucinex DM.

Call your doctor if your symptoms do not improve after 7 days, or if you have a fever, rash, or headaches.

If you need to have any type of surgery, tell the surgeon ahead of time if you have taken this medicine within the past few days.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since Mucinex DM is used when needed, you may not be on a dosing schedule. Skip any missed dose if it’s almost time for your next dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Mucinex DM?

Avoid driving or hazardous activity until you know how Mucinex DM will affect you. Your reactions could be impaired.

Drinking alcohol with this medicine can cause side effects.

Ask a doctor or pharmacist before using other cough or cold medicines that may contain similar ingredients.

Mucinex DM side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

This medicine may cause serious side effects. Stop using this medicine and call your doctor at once if you have:

• mood changes;
• severe headache; or
• severe dizziness or anxiety, feeling like you might pass out;.

Common side effects of Mucinex DM may include:

• dizziness, drowsiness;
• sleep problems (insomnia);
• diarrhea; or
• feeling nervous, restless, anxious, or irritable;.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Mucinex DM?

Avoid using Mucinex DM with other drugs that cause drowsiness or slow your breathing (such as opioid medicine, a muscle relaxer, or medicine for anxiety or seizures).

Ask a doctor or pharmacist before using this medicine if you are also using any other drugs, including prescription and over-the-counter medicines, vitamins, and herbal products. Some medicines can cause unwanted or dangerous effects when used together. Not all possible interactions are listed in this medication guide.

Popular FAQ

Some research suggests that Mucinex may help increase fertility by keeping the cervical mucus thin around the time of ovulation, which ensures sperm can travel freely through the cervix and helps with sperm survival. An increase in fertility can help increase your chances of becoming pregnant. Women with hostile mucus as the only cause of their infertility are the ones most likely to benefit from guaifenesin treatment. Continue reading

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