Hi there, Unienzyme is digestive medicine which has fungal diastase and papain (enzymes to aid digestion). It has negligible side effects and is known to help in cases where the belching is due to indigestion. I would suggest using it for the prescribed time and checking how much relief your father has. Also ask him to Eat in moderation (in case he doesn t already) and avoid fatty, oily and spicy foods. If it solves the problem fine, otherwise other causes like GERD, peptic ulcer, obstruction, etc., will have to be ruled out. Hope this addresses your concern. Reach out to me for any other questions. Regards