 [ Symptoms ] is this a symptom of post nasal drip or something a little more serious  i spent the weekend at a relative is home and they have a cat i am allergic to cats so naturally my eyes were irritated i was sneezing and a bit congested after about a week the sneezing and congestion went away but i began to cough it started off as a dry cough but now after about two weeks it sounds pretty horrible and there is quite a bit of mucus is this a symptom of post nasal drip or something a little more serious [ Disease ] you are right to be concerned what may have started out as an allergy or even a cold may have turned into something more serious coughing up mucous can be caused by the post nasal drip of allergies or sinus infection but it can also be from a cold asthma bronchitis or even pneumonia the only way to know is for your doctor to take a look and listen your symptoms have been going on long enough that you should give your doctor a call you need to find out what is going on and how to get some relief here is a great webmd article on cough that can give you more information hope you feel better soon