Sore Throat and Mucus: What's the SD?

Factual Questions
1

I’ve got me a sore throat and the mucus that keeps collecting in the back of the throat. I’ve noticed two things:

  1. As long as I lay down, I don’t really have any problems.

  2. Once I stand/sit up, I start coughing.

I’m assuming that the cause of this is the mucus shifting down the back of my throat and clogging something-or-other. Once I start coughing, I can feel this stuff dislodge and I stop coughing. The problem is that the back of my throat gets raw and hurts like hell. Water and lozenges help for a little while.

Now, I’ve read both that 1) I need to get rid of this mucus, for whatever reason and 2) I need to keep that mucus there because it’s protecting the…things…that are working to fix whatever might be wrong with the ol’ throat.

So, should I hack this mucus up or keep it around until it disappears on its own?

Thanks for the help.