Disofenin is an iminodiacetic acid derivative with no known pharmacologic actions at the doses recommended. Technetium Tc 99m disofenin injection is a radiopharmaceutical. Technetium Tc99m disofenin is indicated as a hepatobiliary imaging agent. Technetium Tc99m disofenin is indicated in the diagnosis of acute cholecystitis as well as to rule out the occurrence of acute cholecystitis in suspected patients with right upper quadrant pain, fever, jaundice, right upper quadrant tenderness and mass or rebound tenderness, but not limited to these signs and symptoms. Itching at the site of injection progressing to erythema multiforme has been reported following single administration. Also, rare cases of chills and nausea have been reported.