Purpose: To assess the frequency of blood glucose level higher than 150 mg/dL in non-diabetic patients presenting for FDG PET. Methods: We reviewed the electronic medical record ( EMR) of all lymphoma patients who had at least one FDG PET/CT from July 1, 2014 through June 30, 2015. We extracted the blood glucose level at the time of the FDG PET during this 1-year time period and any previous PET scans these patients had. Patients' diabetic status was determined from EMR. Results: One hundred seventeen patients with 574 scans were included: 91 non-diabetic with 429 scans and 26 diabetic patients with 145 scans. Blood glucose level ranged from 44 to 259 mg/dL: 44 to 144 mg/dL in nondiabetic patients and 73 to 259 mg/dL in diabetic patients. There was no non-diabetic patient with a glucose level higher than 150 mg/dL at any occasion. Only one scan was performed with 144 mg/dL of glucose. All other scans were performed with a glucose level less than 140 mg/dL. There were nine diabetic patients with glucose level less than 150 mg/dL prior to all of their scans and 17 diabetic patients with a glucose level higher than 150 mg/dL prior to PET at least on one occasion. Conclusions: In all non-diabetic patients, blood glucose level was below the lower limit of the recommended range prior to all their FDG PET scans while this was not the case in diabetic patients. We conclude that measuring blood glucose level prior to FDG PET may be limited to diabetic patients.