Hi.. Thanks for the query.. As per your complain excessive mucous after removal of tonsils seems to be most commonly due to inflammation in throat causing irritation due to the tonsillectomy procedure that causes inflammation of the tissues .. It stimulate the salivary glands leading to excessive production of mucous.. There is also pain during swallowing that can further reduce swallowing tendency and gives a psychological impression of excessive mucous buildup.. It is a commonly seen problem post tonsillectomy... Acid buildup is due to intake of medications like antibiotics that must be given to him after surgery leading to hyperacidity.. I would suggest you that in case if the mucous is irritating and he is not willing to swallow it then you can get a suction machine and can use it to remove mucous from the mouth and throat.. Drinking plenty of water, doing warm saline gargles will also help in loosening the mucous and ease in its drainage.. Hope this information helps.. Regards.