My 80 yr old mom has chronic cough for 8 yrs.most everytime she eats,she coughs up phlegm.rarely coughs when outside.don't smoke,only med is predisone8mg for polymyalgia,occasional heartburn tecta 40 mg, stuffy nose at times.tickle in throat.pls help?

Look at swallowing!: Chronic cough could be multifactorial and post nasal drainage, some medication such as Lisinopril, airway dehydration are common but in a older person, specially happening after eating you want to look at the esophageal function specially in a patient that takes prednisone for polymyalgia that will increase the risk of aspiration pneumonia. Ask for GI doc that works in esophageal disease.