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Guaifenesin and pseudoephedrine

Generic name: guaifenesin and pseudoephedrine [ gwye-FEN-e-sin, SOO-doe-ee-FED-rin ]
Brand names: Ambifed-G, Entex T, Maxifed, Mucinex D, Mucinex D Max Strength, ... show all 147 brands
Dosage forms: oral capsule (200 mg-30 mg), oral liquid (50 mg-7.5 mg/mL), oral tablet (375 mg-60 mg; 380 mg-60 mg; 400 mg-20 mg; 400 mg-60 mg), ... show all 4 dosage forms
Drug class: Upper respiratory combinations

Medically reviewed by Drugs.com on Jul 26, 2023. Written by Cerner Multum.

What is guaifenesin and pseudoephedrine?

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

Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making it easier to cough out through your mouth.

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

Guaifenesin and pseudoephedrine is a combination medicine used to treat stuffy nose and sinus congestion, and to reduce chest congestion caused by the common cold or flu.

Guaifenesin and pseudoephedrine may also be used for purposes not listed in this medication guide.

Guaifenesin and pseudoephedrine 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.

Guaifenesin and pseudoephedrine may cause serious side effects. Stop using guaifenesin and pseudoephedrine and call your doctor at once if you have:

  • fast, pounding, or uneven heartbeat; or

  • severe anxiety or nervousness.

Common side effects of guaifenesin and pseudoephedrine 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.

Warnings

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Before taking this medicine

You should not use guaifenesin and pseudoephedrine if you are allergic to it.

Do not use guaifenesin and pseudoephedrine 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 it is safe for you to take this medication if you have:

It is not known if this medication may be harmful to an unborn baby. Do not use guaifenesin and pseudoephedrine without medical advice if you are pregnant.

Guaifenesin and pseudoephedrine may pass into breast milk and may harm a nursing baby. Decongestants may also slow breast milk production. Do not use this medicine without medical advice if you are breast-feeding a baby.

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

How should I take guaifenesin and pseudoephedrine?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. Cough or cold medicine is usually taken only for a short time until your symptoms clear up.

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving cough or cold medicine to a child. Death can occur from the misuse of cough or cold medicine in very young children.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

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

The chewable tablet must be chewed before you swallow it.

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

Call your doctor if your symptoms do not improve after 7 days of treatment, or if you have a fever with a headache, cough, or skin rash.

Store at room temperature away from moisture and heat.

Guaifenesin and pseudoephedrine dosing information

Usual Adult Dose for Cough and Nasal Congestion:

Immediate release tablets: 1 tablet orally every 4 hours
Maximum dose: 4 tablets per 24 hours


Extended release (600 mg/ 60 mg) tablets: 2 tablets orally every 12 hours
Maximum dose: 4 tablets per 24 hours


Maximum strength (1200 mg/ 120 mg) extended release tablets: 1 tablet orally every 12 hours
Maximum dose: 2 tablets per 24 hours

Usual Pediatric Dose for Cough and Nasal Congestion:

Immediate release tablets:
12 years and older: 1 tablet orally every 4 hours
Maximum dose: 4 tablets per 24 hours

6 to 12 years: One half tablet orally every 4 hours
Maximum dose: 2 tablets per 24 hours


Extended release (600 mg/ 60 mg) tablets:
12 years and older: 2 tablets orally every 12 hours
Maximum dose: 4 tablets per 24 hours


Maximum strength (1200 mg/ 120 mg) extended release tablets:
12 years and older: 1 tablet orally every 12 hours
Maximum dose: 2 tablets per 24 hours


25 mg/ 7.5 mg/ mL liquid:
2 to under 6 years (11 to 21 kg): 2 mL every 4 to 6 hours
Maximum dose: 4 doses per 24 hours

What happens if I miss a dose?

Since guaifenesin and pseudoephedrine is taken when needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

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 guaifenesin and pseudoephedrine?

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol with guaifenesin and pseudoephedrine can cause side effects.

Ask a doctor or pharmacist before using any other cough, cold, or allergy medicine. Guaifenesin and pseudoephedrine are contained in many combination medicines. Taking certain products together can cause you to get too much of a certain drug.

What other drugs will affect guaifenesin and pseudoephedrine?

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.

Taking this medicine with other drugs that make you sleepy or slow your breathing can worsen these effects. Ask your doctor before taking guaifenesin and pseudoephedrine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

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.