Gastric disorder

My brother has been suffering for the past 10 years from a strange gastric disorder. His illness started suddenly when he was a teenager. His medical tests revealed that his stomach had become very sluggish and slow and as a result, food was staying in it longer than normal. We tried every medicine possible and nothing helped.

We then tried homeopathic medicine. The doctor gave him the most common medicines for stomach ailments such as Nux vomica and Chamomilla but they didn't help much either.

Currently he is still suffering.
* His food intake is very little as he feels full and heavy in the stomach if he eats more.
* He also eats bland and light foods which can be easily digested.
* He has very severe acidity with burning sensation in the stomach and lower abdomen.
*He feels a bit better if he puts ice packs on his stomach and lower abdomen.
* He even has burning sensation when passing stool and his stools feel very warm and acidic.
* Sometimes the stools even have patches of fresh (bright red) blood.
* He gets angry and excited very easily.
* His mood swings regularly.
* He worries a lot and gets upset over small things.
* His mouth and throat also feels very dry.
* He cannot eat foods like biscuit dry. He has to dip them in water or tea.
* He cannot eat even slightly spicy or tangy foods and only eats very bland foods.
* He never had any serious illness before this.
* He was a very bright student always coming first in his class.
* He is a perfectionist and likes everything to be just perfect.
* He was always very tall and thin since he was young

I would greatly appreciate if anyone could please suggest the right homeopathic medicine for his condition. If you need any more info, please don't hesitate to ask. Thank you.