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Mucinex Fast-Max Severe Congestion & Cough

Generic Name: dextromethorphan, guaifenesin, and phenylephrine (dex troe meth OR fan, gwye FEN e sin, fen il EFF rin)
Brand Name: Broncotron-D, Desgen DM (Phenylephrine), Duravent DM, Giltuss, G-Tusicof, Mucinex Fast-Max Severe Congestion & Cough, Phlemex Forte, Robitussin Multi-Symptom Cold, Robitussin Pediatric Cough & Cold CF, Tusicof, Tussin CF, Vanacof DM, Z-tuss DM

Medically reviewed by Drugs.com on Aug 31, 2018 – Written by Cerner Multum

What is Mucinex Fast-Max Severe Congestion & Cough?

There are many brands and forms of Mucinex Fast-Max Severe Congestion & Cough available. Not all brands are listed on this leaflet.

Dextromethorphan is a cough suppressant that affects signals in the brain that trigger cough reflex.

Guaifenesin is an expectorant that loosens congestion in your chest and throat.

Phenylephrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).

Mucinex Fast-Max Severe Congestion & Cough is a combination medicine used to treat cough, stuffy nose, and chest congestion caused by allergies, the common cold, or the flu.

This medicine will not treat a cough that is caused by smoking, asthma, or emphysema.

Mucinex Fast-Max Severe Congestion & Cough may also be used for purposes not listed in this medication guide.

Important Information

Do not use this medicine if you have taken an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

Before taking this medicine

You should not use this medicine if you are allergic to dextromethorphan, guaifenesin, or phenylephrine.

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, phenelzine, rasagiline, selegiline, and tranylcypromine.

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

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

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

How should I take Mucinex Fast-Max Severe Congestion & Cough?

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.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

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

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

If you need surgery or medical tests, tell the surgeon or doctor ahead of time if you have taken this medicine within the past few days.

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

Store at room temperature away from moisture and heat. Do not allow liquid medicine to freeze.

What happens if I miss a dose?

Since cough or cold medicine 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 Fast-Max Severe Congestion & Cough?

Drinking alcohol with this medicine can cause side effects.

This medicine may cause blurred vision and may impair your reactions. Avoid driving or hazardous activity until you know how this medicine will affect you.

Drinking alcohol can increase certain side effects of this medicine.

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

Mucinex Fast-Max Severe Congestion & Cough 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.

Stop using this medicine and call your doctor at once if you have:

  • little or no urination;

  • fast or slow heartbeats;

  • confusion, severe dizziness, feeling unsteady;

  • severe nausea or vomiting;

  • severe headache, blurred vision, pounding in your neck or ears;

  • slow breathing; or

  • unusual changes in mood or behavior.

Common side effects may include:

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 Fast-Max Severe Congestion & Cough?

Some medicines can cause unwanted or dangerous effects when used together. Avoid using Mucinex Fast-Max Severe Congestion & Cough 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 any other medication, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

More about Mucinex Fast-Max Severe Congestion & Cough (dextromethorphan / guaifenesin / phenylephrine)

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