Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making it easier to cough out through your mouth.
Guaifenesin is used to reduce chest congestion caused by the common cold, infections, or allergies.
Guaifenesin may also be used for purposes not listed in this medication guide.
Important information
You should not use guaifenesin if you are allergic to guaifenesin.
Use guaifenesin exactly as directed on the label, or as prescribed by your doctor. Do not use it in larger amounts or for longer than recommended.
Do not give guaifenesin to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children. Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking this medication. This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Before taking this medicine
You should not use this medicine if you are allergic to guaifenesin. FDA pregnancy category C. It is not known whether guaifenesin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. It is not known whether guaifenesin passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
How should I take guaifenesin?
Use guaifenesin exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.
Do not give guaifenesin to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children. Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking this medication. Take guaifenesin with food if it upsets your stomach.
Measure the liquid form of guaifenesin with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.
Do not crush, chew, break, or open a controlled-release, delayed-release, or extended-release tablet or capsule. Swallow it whole. Breaking or opening the pill may cause too much of the drug to be released at one time.
Store guaifenesin at room temperature away from moisture, heat, and direct sunlight.
What happens if I miss a dose?
Since cough medicine is taken when needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid?
This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Guaifenesin side effects
Get emergency medical help if you have any of these signs of an allergic reaction to guaifenesin: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Less serious guaifenesin side effects may include:
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
Guaifenesin dosing information
Usual Adult Dose of Guaifenesin for Cough:
Immediate release formulation: 200 to 400 mg orally every 4 hours as needed, not to exceed 2.4 g/day
Sustained release formulation: 600 to 1200 mg orally every 12 hours, not to exceed 2.4 g/day
Usual Pediatric Dose of Guaifenesin for Cough:
Immediate release formulation:
less than 2 years: 12 mg/kg/day orally in 6 divided doses
2 to 5 years: 50 to 100 mg orally every 4 hours as needed, not to exceed 600 mg/day
6 to 11 years: 100 to 200 mg orally every 4 hours as needed, not to exceed 1.2 g/day
12 years or older: 200 to 400 mg orally every 4 hours as needed, not to exceed 2.4 g/day
Sustained release formulation:
2 to 5 years: 300 mg orally every 12 hours, not to exceed 600 mg/day
6 to 11 years: 600 mg orally every 12 hours, not to exceed 1.2 g/day
12 years or older: 600 to 1200 mg orally every 12 hours, not to exceed 2.4 g/day
What other drugs will affect guaifenesin ?
There may be other drugs that can interact with guaifenesin. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.
