I have had persistent coughing for the last month. what symptoms indicate that i need a doctor's appointment? i have been coughing up a lot of yellow-greenish thick mucus. sometimes i feel a rattling in my chest when i inhale, but sometimes i don't. it se

Any : Any cough that lasts longer than 2 weeks should be evaluated by a doctor. You could have a bacterial super-infection or a hypersensitive lung reaction (like asthma) on what started out as a cold a month ago. Give your doctor a call - hopefully with a good history and exam, they'll get to the bottom of your cough and have you feeling better in no time. Good luck!