Guaifenesin ( gwye-FEN-e-sin) is used to help coughs caused by colds or similar illnesses clear mucus or phlegm (pronounced flem) from the chest. It works by thinning the mucus or phlegm in the lungs.
Another commonly used name is glyceryl guaiacolate.
The dose of guaifenesin will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of guaifenesin. If your dose is different, do not change it unless your doctor tells you to do so.
For regular (short-acting) oral dosage forms (capsules, oral solution, syrup, or tablets):
Adults?200 to 400 milligrams (mg) every four hours.
Children younger than 2 years of age?Use and dose must be determined by your doctor.
Children 2 to 6 years of age?50 to 100 mg every four hours.
Children 6 to 12 years of age?100 to 200 mg every four hours.
For long-acting oral dosage forms (extended-release capsules or tablets):
Adults?600 to 1200 mg every twelve hours.
Children younger than 2 years of age?Use is not recommended.
Children 2 to 6 years of age?300 mg every twelve hours.
Children 6 to 12 years of age?600 mg every twelve hours.
If you must take this medicine regularly and you miss a dose, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
To store this medicine:
Keep out of the reach of children.
Store away from heat and direct light.
Do not store the capsule or tablet form of this medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
Do not refrigerate the syrup form of this medicine.
Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.
Precautions While Using This Medicine
If your cough has not improved after 7 days or if you have a fever, skin rash, continuing headache, or sore throat with the cough, check with your doctor. These signs may mean that you have other medical problems.
Side Effects of This Medicine
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine.
However, check with your doctor if any of the following side effects continue or are bothersome:
Less common or rare
Diarrhea; dizziness; headache; hives; nausea or vomiting; skin rash; stomach pain
Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.
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