my dad has had severe abdominal pains for months now, he is constanlty belching and is sick or feels sick alot of the time. Its worse after he has eaten.

He has had blood tests and CT scans but they all come back negative. he is in his 50s and eats salads most week days but enjoys meals out and drinks at the week ends. he is active and has never been ill before.

He has had a biopsy of his intestine because his son has celaic desease but that also came back negative.

Any idea as to what could be making his life so miserable!