My daughter has had severe blockage because she was not drinking enough when she was around 7 years old. After that she developed lactose-intolerance which was diagnosed as psycho-somatic pain for years. She knows most there is to know about abdominal pain. I asked her. She said that what would not hurt, regardless the cause: to drink a lot, preferably water or herbal tea, anything not containing stimulants for the intestines. Also very important as she recalls was keeping the stomach warm. Going out of a warm house and stepping into the shade could already bring cramps at one point. Fish-oil is wholesome for the intestines no matter what.

In order to say anything more she would have to know whether he has diarrhea, whether he has trouble eating, etc. Then maybe she might have another non-medical tip for you to help him see it through as comfortably as possible until you see the specialist.