I have a niece born in 1999 (22 years old), with HP disease. After the treatment period is over, my niece eats very little, if she eats a lot, it's easy to vomit. Eat foods such as beef and pork are not allowed and drink less water, sometimes 5% glucose intravenous infusion. The doctor told me that after HP treatment, if the patient eats less, eats a lot, is it okay to vomit?

About a month ago, the upper part of my stomach was constantly in pain, afraid of food and could not eat as much as before. After eating a little, I feel full. In the last 2-3 days, my lower right abdomen hurts again, the condition is very bad. Doctor tell me what is the sign of stomach cramps with little eating? Thank you.