I Have Chronic Stomach Illness, Often I Get Upper Abdominal

I have chronic stomach illness, often i get upper abdominal pain, with sour burrp, stomach filled with gas and the pain increases subsides only when i vomit or get intravenal injections. I able to predict this is going to happen when the sour burrp starts, i told the doctor the same that i know wen it starts can i imeediately take some medicines to stop before it gets worse. Kindly help me out in this. It occurs mostly during the nights very rarely i had this happen in day.