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Dextromethorphan and guaifenesin

Generic name: dextromethorphan and guaifenesin [ DEX-troe-me-THOR-fan-and-gwye-FEN-e-sin ]
Brand names: Adult Cough DM, Children Giltuss Cough and Chest Congestion, Children's Delsym Cough+Chest Congest DM, Children's Robitussin Cough and Chest, Children's Robitussin Cough and Chest Congestion DM, ... show all 229 brands
Dosage forms: oral capsule (10 mg-200 mg), oral granule (5 mg-100 mg), oral liquid (10 mg-100 mg/10 mL; 10 mg-100 mg/5 mL; 10 mg-187 mg/5 mL; 10 mg-200 mg/5 mL; 15 mg-200 mg/5 mL; 20 mg-200 mg/10 mL; 20 mg-200 mg/20 mL; 20 mg-400 mg/20 mL; 20 mg-400 mg/5 mL; 5 mg-100 mg/5 mL), ... show all 5 dosage forms
Drug class: Upper respiratory combinations

Medically reviewed by Drugs.com on Jul 27, 2023. Written by Cerner Multum.

What is dextromethorphan and guaifenesin?

Dextromethorphan is a cough suppressant. Guaifenesin is an expectorant.

Dextromethorphan and guaifenesin 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.

Dextromethorphan and guaifenesin may also be used for purposes not listed in this medication guide.

Dextromethorphan and guaifenesin 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.

dextromethorphan and guaifenesin may cause serious side effects. Stop using dextromethorphan and guaifenesin 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 dextromethorphan and guaifenesin 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.

Dextromethorphan / guaifenesin side effects (more detail)

Warnings

Do not use this medicine 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 dextromethorphan and guaifenesin 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:

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 dextromethorphan and guaifenesin?

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 this medicine.

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.

Detailed Dextromethorphan / guaifenesin dosage information

What happens if I miss a dose?

Since dextromethorphan and guaifenesin 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 dextromethorphan and guaifenesin?

Avoid driving or hazardous activity until you know how dextromethorphan and guaifenesin 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.

What other drugs will affect dextromethorphan and guaifenesin?

Avoid using this medicine 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.

Dextromethorphan / guaifenesin drug interactions (more detail)

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.

Medical Disclaimer

Copyright 1996-2023 Cerner Multum, Inc. Version: 8.01.