Dextromethorphan is a cough suppressant. It affects the signals in the brain that trigger
cough reflex.
Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making
it easier to cough out through your mouth.
Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages.
Dilated blood vessels can cause nasal congestion (stuffy nose).
The combination of dextromethorphan, guaifenesin, and pseudoephedrine is used to treat
stuffy nose, sinus congestion, cough, and chest congestion caused by the common cold or flu.
Dextromethorphan will not treat a cough that is caused by smoking, asthma, or
emphysema.
Dextromethorphan, guaifenesin, and pseudoephedrine may also be used for other
purposes not listed in this medication guide.