I am a teacher and a singer, and have a years long condition of sinus congestion, not caused by allergy, just constant. I am taking Claritin D which greatly reduces the amount of congestion in my sinuses, and frees me from constantly having to wipe a runny nose. But it doesn't treat another years long condition, that of having to always clear congestion in my vocal chords, to be able to simply say "hello" clearly when the phone rings. The vocal chord congestion is a constant hurdle I have to clear to be able to teach or sing. My doctor offered no remedy. Could Guaifenesen help with the throat clearing? It would be so wonderful to just be able to simply talk easily! And, if it helps, can I take it indefinitely? Thanks.