Coughing up mucus what's the cause?

Since I'm taking cough medicine, I've been coughing up mucus.
What's the cause? Is it the sign of feeling better? Or is the coughing loosening up? I've been taking robatussan which has been helping quite allot. Could that cause mucus?
I'm just...

wondering.

You should be coughing it up - and spitting it out. You need to get that out of your body.

**Is it the sign of feeling better? or is the coughing loosening up?**

Yes.

**I've been taking Robatussan which has been helping quite allot. Could that cause mucus? **

No, your cough probably started as a sore throat. Mucous is a by-product of it.

 
I think mucus is caused by your lungs trying to fight off infection. The Robatussan is helping your body expel the mucus along with the trapped infectious organisms.

If your throat is sore, try sucking down a couple tablespoons of honey. It not only helps soothe the throat but helps kill any germs in your throat.

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