★★★★☆
Caution: this mixture WILL bubble and splatter unless the Vicks is mixed in SLOWLY.
I heat a coffee cup of water to near boiling. Then slowly and carefully I dip a half teaspoon of Vicks into the cup just a little at a time while breathing the vapors into my nose. At first you have to go VERY SLOW or the mixing with bubble over and make a big mess. When I first did this there was some burning sensation, but it causes a lot of mucus to run and seems to open things up.
It has NOT been a cure all, but it is one thing I do and it might be a ready source of EUCALYPTUS OIL (at a low concentration) for those who want to try it without hunting around.