A nasojejunal (NJ) tube is a thin, tender tube this is installed via the nostril, goes through the belly and ends in the jejunum (jue-joo-num), a part of the small gut.

After numbing gel is positioned on the nose a small tube could be guided down the nose and into the jejunum (small bowel) the use of fluoroscopic (X-ray) guidance. To assist visualize the belly and small bowel, a small quantity of comparison (X-ray dye) could be injected through the tube.