Skip to main content

Entex T

Generic name: guaifenesin and pseudoephedrinegwye-FEN-e-sin, SOO-doe-ee-FED-rin ]
Brand names: Ambifed-G, Entex T, Maxifed, Mucinex D, Mucinex D Max Strength, ... show all 15 brands
Drug class: Upper respiratory combinations

Medically reviewed by Drugs.com on Oct 11, 2023. Written by Cerner Multum.

What is guaifenesin and pseudoephedrine?

Guaifenesin and pseudoephedrine is a combination medicine used in adults and children to treat allergy symptoms such as runny or stuffy nose, sneezing, watery eyes, itching of nose and throat, cough with mucus, sinus pain, and to reduce chest congestion caused by the common cold, hay fever, or other allergies.

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

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:

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 use guaifenesin and pseudoephedrine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, and tranylcypromine.

Taking more than your recommended dose will not make this medicine more effective, and may cause serious side effects.

Before taking this medicine

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

Tell your doctor if you have or have ever had:

Tell your doctor if you are pregnant or breastfeeding.

Do not give this medicine to a child without medical advice.

How should I take guaifenesin and pseudoephedrine?

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

Follow all directions when giving this medicine to a child. Do not use the medicine to make a child sleepy. Misuse of this medicine may cause death in very young children.

Taking more than your recommended dose will not make this medicine more effective, and may cause serious side effects.

Measure liquid medicine with the supplied measuring device (not a kitchen spoon).

Swallow the extended release tablet whole and do not crush, chew, or break it. Take with a full glass of water.

Your dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using exactly as directed on the label, or as prescribed by your doctor.

Stop using this medicine and call your doctor if your symptoms do not improve or get worse after 7 days, or if you also have a fever, rash, or headaches.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Guaifenesin and pseudoephedrine is used when needed. If you are on a dosing schedule, skip any missed 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 guaifenesin and pseudoephedrine?

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

What other drugs will affect guaifenesin and pseudoephedrine?

Ask a doctor or pharmacist before using any other medicines that can cause drowsiness (such as opioid medication, sleep medicine, a muscle relaxer, or medicine for anxiety or seizures). Tell your doctor about all other medicines you use. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

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.