 A whole-body PET CT scan is performed to identify and understand the functioning of your tissues and organs. On the day of the scan, please do not take diabetic medication or injections. However, other medications may be taken. A 5-hour fast is also required. Please carry all your medication reports and inform the attending nurse or physician of any history of contrast allergy or if you are pregnant. During the scan, a small dose of radioactive injection is given intravenously and whole-body scan is done one hour later. The initial part of the scan is a diagnostic CT wherein intravenous contrast is given, followed by PET imaging. All this takes around 10-12 minutes. A blood test, serum creatinine is mandatory prior to the scan if the doctor has advised for a contrast CT. A test report should not be more than two months old. Please stay away from pregnant women for a day after the scan. Reports will be issued the next day.