Guaifenesin (By mouth)

Guaifenesin (gwye-FEN-e-sin)

Thins mucus so you can clear it from your head, throat, and lungs.

Brand Name(s):

Allfen, Chest Congestion Relief, Children's Mucus Relief, Diabetic Siltussin DAS-Na, Diabetic Tussin, Equaline 12HR Mucus-ER, Equate Mucus ER, Geri-Tussin, Good Neighbor Pharmacy Children's Mucus Relief, Good Neighbor Pharmacy Mucus ER, Good Neighbor Pharmacy Mucus Relief, Good Neighbor Pharmacy Tab Tussin, Good Neighbor Pharmacy Tussin, Good Neighbor Pharmacy Tussin Chest Congestion, Good Sense Mucus Relief

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have ever had an allergic reaction to guaifenesin. Do not give any over-the-counter (OTC) cough and cold medicine to a baby or child under 4 years old. Using these medicines in very young children might cause serious or possibly life-threatening side effects.

How to Use This Medicine:

Capsule, Tablet, Long Acting Capsule, Long Acting Tablet, Liquid

  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • Follow the instructions on the medicine label if you are using this medicine without a prescription.
  • Measure the oral liquid medicine with a marked measuring spoon, oral syringe, or medicine cup.
  • Do not break, chew, or crush the tablet or capsule. Swallow it whole with a full glass of water.

If a dose is missed:

  • You must use this medicine on a fixed schedule. Call your doctor or pharmacist if you miss a dose.

How to Store and Dispose of This Medicine:

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Do not freeze the oral liquid.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

Warnings While Using This Medicine:

  • If you are pregnant or breast feeding, ask your doctor or pharmacist before using this medicine.
  • If your cough is caused by asthma, emphysema, bronchitis, or smoking, talk to your doctor before using this medicine.
  • This medicine may contain alcohol.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Cough that lasts longer than 7 days.
  • Cough with fever, skin rash, or ongoing headache.

If you notice these less serious side effects, talk with your doctor:

  • Drowsiness.
  • Nausea, vomiting, diarrhea, stomach pain.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 11/6/2020

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