I had an Upper GI with small bowel follow through today for constipation. It took 4 hours for the barium to pass and enter my pouch. Does anyone know what the average transit time is for the small intestines when without large intestines? Also, does the small intestine slow down or speed up when they are functioning as large intestines as well. The Radiologist said the test was 4 hours long and the small intestine and pouch was fine. I was just concerned over the transit time.