Guaifenesin Uses

Guaifenesin is an over-the-counter expectorant that is used to treat symptoms of chest congestion. 

There may be other uses of guaifenesin —your doctor or pharmacist can give you further drug information.

Guaifenesin Mechanism of Action

Guaifenesin works by thinning or loosening mucus and making it easier to cough up, thereby helping to clear the air passages. 

Guaifenesin Doses

Guaifenesin is available as 200 mg and 400 mg tablets, 600 mg and 1,200 mg extended-release tablets, 100 mg dissolvable granules, and 100 mg/5 mL oral solution (liquid). The usual dose of guaifenesin in different age groups is as follows:

Adults and children 12 years of age and older: 200 mg to 400 mg every 4 hours as needed. Maximum dose 2,400 mg per day.

Children between 6 and 12 years of age: 100 mg to 200 mg every 4 hours as needed. Maximum dose 1,200 mg per day.

Children between 4 and 6 years of age: 50 mg to 100 mg every 4 hours as needed. Maximum dose 600 mg per day.

The extended-release tablet of guaifenesin is for adults and children 12 years of age and older. The dose is 1-2 tablets every 12 hours with a maximum of 2,400 mg in 24 hours.