My lab has always had a sensitive stomach it seems, in that he used to get the runs pretty easily. He throws up often (sometimes several times a week). I have tried to find the trigger but can’t. I shifted meal times around, I feed 2 meals rather than 1. I tried bedtime snack incase it was his stomach being empty. I can’t bulk up a meal or add a chew to a full meal or he barfs it up. Sometimes it’s just foamy bile, other times it’s his food. He has been on probiotics off and on all his life, and on high end food. I have even tried Antacid tabs which do seem to help sometimes, he at least can hold it till morning most times now.
The first thing would be to have a physical performed and bloodwork to rule out pancreatitis.
Meanwhile try raw food as it is easier to digest. or a bland diet such as raw eggs and cooked oatmeal. My favorite herbal supplement for gastric upset is phytomucil by animal apawthecary, but I feel there is deep chronic disease to blame for the symptoms here and homeopathy by a trained veterinary homeopath is your best bet.
Yours in health,