FM/CFS/ME RESOURCES - Drug Database - Guaifenesin


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Drug Database - Guaifenesin Guaifenesin 600 mg. tablet

Generic Name: guaifenesin (gwye-FEN-eh-sin)

Brand Names: Mucinex®

Classification: Expectorant

Issue Date: 1987

Guaifenesin is used for relieving symptoms of cough and mucus in the chest due to colds, flu, or hay fever. It is also used in treating the symptoms of FM. Guaifenesin is an expectorant. 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.

Guaifenesin is also used to treat fibromyalgia symptoms by removing excess phosphate from the body, which Dr. St. Amand believes to be the cause of fibromyalgia. The removal of the phosphate would supposedly lead to a reversal of all fibromyalgia symptoms, which would essentially be as close to a cure as possible.

  • Before Using This Medicine
  • How To Use This Medicine
  • Precautions While on this Medicine
  • Side Effects
  • If You Miss A Dose
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    Before Using This Medicine

    Some medical conditions may interact with Guaifenesin. Tell your doctor or pharmacist 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 a chronic cough that occurs with smoking, asthma, chronic bronchitis, or emphysema
    • if cough occurs with large amounts of mucus

    This may not be a complete list of all interactions that may occur. Ask your health care provider if Guaifenesin 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.

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    How To Use This Medicine

    Use Guaifenesin as directed by your doctor. Check the label on the medicine for exact dosing instructions.

    Guaifenesin may be taken with or without food. Drinking extra fluids while you are taking Guaifenesin is recommended. Check with your doctor for instructions.

    Swallow Guaifenesin whole. Do not break, crush, or chew before swallowing. Ask your health care provider any questions you may have about how to use Guaifenesin.

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    Precautions While on this Medicine

    Guaifenesin may cause dizziness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Guaifenesin. Using Guaifenesin 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.

    Safety in CHILDREN and instructions for use differs according to the brand used. Talk to you doctor or pharmacist if you have any questions about the brand you are using.

    PREGNANCY and BREAST-FEEDING: If you plan on becoming pregnant, discuss with your doctor the benefits and risks of using Guaifenesin during pregnancy. It is unknown if Guaifenesin is excreted in breast milk. If you are or will be breast-feeding while you are using Guaifenesin, check with your doctor or pharmacist to discuss the risks to your baby.

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    If You Miss A Dose

    If you miss a dose of Guaifenesin 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.

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    Side Effects

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

    • skin rash or hives
    • difficulty breathing
    • swelling of your face, lips, tongue, or throat

    Check with your doctor if any of these most COMMON side effects persist or become bothersome:

    • Diarrhea
    • dizziness
    • gas
    • headache
    • nausea
    • upset stomac
    • vomiting
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