As far as what Dawn said, what you are looking for is mucinex...... now... a bit of a warning....
Be sure to drink PLENTY of water with the mucinex.... it says that on the box.
The mucinex will also MAKE you cough more, since it is getting rid of the phlegm and mucus..... so there is a Mucinex DM (the DM is the dextromethorphan, which is a cough suppressant).... so it will seem like the medicine is "making you worse" .....
It does help, but it takes a while.
Of course, if you really are feeling worse, or start running a fever, go see the doctor. I've had pneumonia a few times, so I know you don't want to mess with that! (My trial with pneumonia started with mycoplasmal pneumonia, I took the medicine for the 10 days, and 3 days later ended up with bacterial pneumonia... that one REALLY threw me for a loop...)
Winter here in Texas this year is really being a bit strange... there may be more allergens out that you aren't used to, also.....