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Guaifenesin/ potassium guaiacolsulfonate

Generic Name: guaifenesin/potassium guaiacolsulfonate (gwye-FEN-eh-sin/poe-TASS-ee-um gwye-a-kole-SUL-foe-nate)
Brand Name: Allfen and Humibid LA

Guaifenesin/ potassium guaiacolsulfonate is used for:

Relieving symptoms of cough and mucus in the chest due to respiratory infections, asthma, colds, or hay fever. It may also be used for other conditions as determined by your doctor.

Guaifenesin/potassium guaiacolsulfonate is a combination of 2 expectorants. It works by thinning mucus (phlegm) in the lungs and making it less sticky and easier to cough up. This reduces chest congestion by making coughs more productive.

Do NOT use guaifenesin/ potassium guaiacolsulfonate if:

  • you are allergic to any ingredient in guaifenesin/potassium guaiacolsulfonate

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

Before using guaifenesin/ potassium guaiacolsulfonate:

Some medical conditions may interact with guaifenesin/potassium guaiacolsulfonate. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning 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 a chronic cough that occurs with smoking, asthma, chronic bronchitis, or emphysema, or if cough occurs with large amounts of mucus

Some MEDICINES MAY INTERACT with guaifenesin/potassium guaiacolsulfonate. Tell your health care provider if you are taking any other medicines. However, no specific interactions with guaifenesin/potassium guaiacolsulfonate are known at this time.

This may not be a complete list of all interactions that may occur. Ask your health care provider if guaifenesin/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 guaifenesin/ potassium guaiacolsulfonate:

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

  • Guaifenesin/potassium guaiacolsulfonate may be taken with or without food.
  • Drinking extra fluids while you are taking guaifenesin/potassium guaiacolsulfonate is recommended. Check with your doctor for instructions.
  • Swallow guaifenesin/potassium guaiacolsulfonate whole. Do not break, crush, or chew before swallowing.
  • If you miss a dose of guaifenesin/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. Do not take 2 doses at once.

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

Important safety information:

  • Guaifenesin/potassium guaiacolsulfonate may cause dizziness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to guaifenesin/potassium guaiacolsulfonate. Using guaifenesin/potassium guaiacolsulfonate alone, with certain other medicines, or with alcohol may lessen your ability to drive or to perform other potentially dangerous tasks.
  • If cough persists for more than 1 week or is accompanied by a fever, contact your health care provider. A persistent cough could be a sign of a serious condition.
  • Guaifenesin/potassium guaiacolsulfonate may interfere with some lab tests. Make sure your doctor and lab personnel know you are taking guaifenesin/potassium guaiacolsulfonate.
  • Use guaifenesin/potassium guaiacolsulfonate with extreme caution in CHILDREN younger than 12 years of age. Safety and effectiveness in this age group have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using guaifenesin/potassium guaiacolsulfonate during pregnancy. It is unknown if guaifenesin/potassium guaiacolsulfonate is excreted in breast milk. If you are or will be breast-feeding while you are using guaifenesin/potassium guaiacolsulfonate, check with your doctor or pharmacist to discuss the risks to your baby.

Possible side effects of guaifenesin/ 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; headache; nausea; upset stomach; vomiting.

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); lower back or side pain.

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. You may report side effects to FDA at 1-800-FDA-1088. You may also report side effects at .

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.

Proper storage of guaifenesin/potassium guaiacolsulfonate:

Store guaifenesin/potassium guaiacolsulfonate at room temperature between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep guaifenesin/potassium guaiacolsulfonate out of the reach of children and away from pets.

General information:

  • If you have any questions about guaifenesin/potassium guaiacolsulfonate, please talk with your doctor, pharmacist, or other health care provider.
  • Guaifenesin/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 is a summary only. It does not contain all information about guaifenesin/potassium guaiacolsulfonate. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

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.