little doggie
this is just my observation when my ger has phlgem...am not a doc so dun quote me. i used to observe if the "phlgem" was from the nose or lungs... there is a difference bcos if the phlgem was produced by the nose, strictly speaking, its a congestion and can be cleared by anti-histamines. if it is caused by the lungs aka infection of the airways, you will need to take meds that help to stop the infection of the airways like ventolin syrup, etc.
actually, by listening to ur boy, u maybe able to tell where his congestion is from.