Thanks for posting your query.
With the available described symptoms, there appears to be possibility of peptic ulcer disease
Presence of severe abdominal pain
, vomiting and burps suggests the diagnosis.
You should consult with internal medicine specialist/ gastroenterologist and should go for thorough check up.
Other possibilities could be acute pancreatitis
, cholecystitis and ketoacidosis.
He should go for complete blood count
, serum amylase, liver function test and ultrasound imaging.
He should also go for endoscopy for better clarification.
He should take proton pump inhibitors along with prokinetics.
He should also take opioid analgesics and antacids.
Exact treatment depends on the diagnosed disease.
Dr. Mayank Bhargava