Is it dangerous to have phlegm over 5 days from the common cold?

Answer 1

No. Its just your lungs continuing to get rid of the rubbish.

Answer 2

I had that problem with a cold once for almost 2 weeks but I didn't have any high fever or anything and it finally went away. I have read that if you have too much congestion it can turn into meningitis. But i think that's kind of rare.