Does anyone cough up very thick clear, foamy phlem or mucus? My husband does and it interfers with eating, sleeping, talking, just about everything. What could this be from? His cancer returned for a 2nd time and he started chemo again. He's had 2 treatments so far. He is very weak and tired. He can drink with no problem. He drinks a lot of milk, he does Boost, OJ, tomato juice, water, etc., but he has problems with food. The food has to be mushed or very small. Sometimes he gets a little bit down but he he trys one more bit he gags. Any thoughts??