Abdominal ultrasound of the gelding with tympanic colic as a result of anaphylactic reaction to sodium ceftriaxone. Image obtained by ventral-abdominal positioning of the probe, caudal to xiphoid. Note the thickening of intestinal wall, distention, atony and ileus in segments of the small intestine. Diagnostic Imaging Sector - FCAV - UNESP - Jaboticabal