My husband was diagnosed with stage 4 esophagus cancer August 2021 he has the same problem when he eats and drinks.
The Dr. Recent had a PET scan done and said everything was going looking good, but my husband still has trouble swallowing at times plus he has right sided nagging pain under his armpit below where his chemo port.
I have looked for ways to reduce the phlegm production, don't know that I could get him to take anything else because he has so much he is doing now. 😢