Skip to Content

The originating document has been archived. We cannot confirm the completeness, accuracy and currency of the content.

Dextromethorphan/ potassium guaiacolsulfonate

Generic Name: dextromethorphan/potassium guaiacolsulfonate (DEX-troe-meth-OR-fan/poe-TASS-ee-um gywe-a-kole-SUL-foe-nate)
Brand Name: Examples include Guiadex DM and Prolex DM

Dextromethorphan/ potassium guaiacolsulfonate is used for:

Temporarily relieving cough due to minor throat and airway irritation associated with upper respiratory tract infections or inhaled irritants.

Dextromethorphan/potassium guaiacolsulfonate is a combination of an expectorant and a cough suppressant. It works by loosening mucus and lung secretions in the chest and making coughs more productive.

Do NOT use dextromethorphan/ potassium guaiacolsulfonate if:

  • you are allergic to any ingredient in dextromethorphan/potassium guaiacolsulfonate
  • you have taken a monoamine oxidase (MAO) inhibitor (eg, selegiline) within the last 14 days
  • you are taking a selective serotonin reuptake inhibitor (SSRI) (eg, fluoxetine)

Contact your doctor or health care provider right away if any of these apply to you.

Before using dextromethorphan/ potassium guaiacolsulfonate:

Some medical conditions may interact with dextromethorphan/potassium guaiacolsulfonate. Tell your health care provider if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, plan to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have chronic cough, chronic bronchitis, or any breathing problems, such as asthma, emphysema, or chronic obstructive pulmonary disease (COPD)

Some MEDICINES MAY INTERACT with dextromethorphan/potassium guaiacolsulfonate. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • MAO inhibitors (eg, selegiline) and SSRIs (eg, fluoxetine) because the risk of toxic side effects may be increased by dextromethorphan/potassium guaiacolsulfonate

This may not be a complete list of all interactions that may occur. Ask your health care provider if dextromethorphan/potassium guaiacolsulfonate may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use dextromethorphan/ potassium guaiacolsulfonate:

Use dextromethorphan/potassium guaiacolsulfonate as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Dextromethorphan/potassium guaiacolsulfonate may be taken with or without food. Take with food if stomach upset occurs.
  • Use a measuring device marked for medicine dosing. Ask your pharmacist for help if you are unsure of how to measure this dose.
  • To help dextromethorphan/potassium guaiacolsulfonate work, drink plenty of extra fluids while taking dextromethorphan/potassium guaiacolsulfonate, unless your health care provider instructed otherwise.
  • If you miss a dose of dextromethorphan/potassium guaiacolsulfonate and you are taking it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule.

Ask your health care provider any questions you may have about how to use dextromethorphan/potassium guaiacolsulfonate.

Important safety information:

  • Dextromethorphan/potassium guaiacolsulfonate may cause drowsiness, dizziness, blurred vision, or lightheadedness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to dextromethorphan/potassium guaiacolsulfonate. Using dextromethorphan/potassium guaiacolsulfonate alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
  • If your cough lasts for more than 1 week or comes back, or if you also have a fever, rash, or persistent headache, contact your health care provider. A persistent cough could be a sign of a serious condition.
  • Dextromethorphan/potassium guaiacolsulfonate contains dextromethorphan. Before you being taking any new prescription or nonprescription medicine, read the ingredients to see if it also contains dextromethorphan. If it does or if you are not sure, contact your health care provider or pharmacist.
  • Diabetes patients - Some brands of dextromethorphan/potassium guaiacolsulfonate may contain sugar and affect your blood sugar level. Read the label carefully before using dextromethorphan/potassium guaiacolsulfonate.
  • Dextromethorphan/potassium guaiacolsulfonate is not recommended for use in CHILDREN younger than 3 years of age. Safety and effectiveness in this age group have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant while taking dextromethorphan/potassium guaiacolsulfonate, discuss with your doctor the benefits and risks of using dextromethorphan/potassium guaiacolsulfonate during pregnancy. It is unknown if dextromethorphan/potassium guaiacolsulfonate is excreted in breast milk. If you are or will be breast-feeding while you are using dextromethorphan/potassium guaiacolsulfonate, check with your doctor or pharmacist to discuss the risks to your baby.

Possible side effects of dextromethorphan/ potassium guaiacolsulfonate:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Dizziness; drowsiness; stomach upset.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue).

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include confusion; excitement; hallucinations; slowed breathing.

Proper storage of dextromethorphan/potassium guaiacolsulfonate:

Store dextromethorphan/potassium guaiacolsulfonate at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep dextromethorphan/potassium guaiacolsulfonate out of the reach of children and away from pets.

General information:

  • If you have any questions about dextromethorphan/potassium guaiacolsulfonate, please talk with your doctor, pharmacist, or other health care provider.
  • Dextromethorphan/potassium guaiacolsulfonate is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take dextromethorphan/potassium guaiacolsulfonate or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about dextromethorphan/potassium guaiacolsulfonate. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to dextromethorphan/potassium guaiacolsulfonate. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using dextromethorphan/potassium guaiacolsulfonate.

Issue Date: June 3, 2015

Further information

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