my kid has sinus... and he´s often prescribed guaifenesin but to help with his cough...

one other treatment is cetirizina (not sure in english)... but that´s for a month or so... hasn´t had for a while... but he used to have chronic sinus and always seemed like flu...

just now he´s coughing and on the guaifenesin for a couple days along with some expectorant to help get rid of the mucus...

I´ve heard that tylenol sinus works pretty good too...