Thanks for writing your query.
After reading your post, it seems that his symptoms are due to Gastro Esophageal Reflux Disease
may be helpful to confirm the diagnosis.
I would advise that he should take an antacid like Omeprazole
40mg once a day before meals along with Domperidone
Following precautions will be helpful :-
1.Avoid spicy and oily foods.
2.Avoid being empty stomach for long periods.
3.Avoid mental and emotional stress.
4.Avoid smoking and alcohol, if any.
5.Avoid self medications, especially pain killers and steroids
6.Avoid gas producing foods like peas, cabbage, legumes, etc.
7.Avoid eating fast and talking while eating.
I hope this is helpful to you.