Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making it
easier to cough out through your mouth.
Theophylline is a bronchodilator. Theophylline works in several ways: It relaxes muscles in your
lungs and chest to increase airflow, decreases the sensitivity of your lungs to allergens and other
substances that cause inflammation, and increases the contractions of your diaphragm so that more air is
drawn into the lungs.
The combination of guaifenesin and theophylline is used to treat symptoms of asthma, bronchitis,
and emphysema.
Guaifenesin and theophylline may also be used for other purposes not listed in this medication
guide.