my daughter had the same problem, except hers was in her chest and throat... I tried all sorts of stuff, baby Vicks on her feet helped the chest congestion, however nothing would get it out of her throat unfortunately for me at 4 in the morning one day right after a feed she threw up, not just spit up I mean it was everywhere, on me (my clothes were soaked, it was in my hair and all down my back) on the rug that her bed sits on, all over her one arm and her blanket.... it was all phlegm and a little milk it seemed... she felt better after that however last nite she was up every 2 1/2 - 3 hours when normally thru the night she goes 5-6 hours.... have you tried sitting in a steamy bathroom to break it up?