The Full Form of FDG is Fluorodeoxyglucose.

Fluorodeoxyglucose (¹⁸F) (INN), or fluorodeoxyglucose F 18 (USAN and USP), also commonly called fluorodeoxyglucose and abbreviated [¹⁸F]FDG, ¹⁸F-FDG or FDG, is a radiopharmaceutical used in the medical imaging modality positron emission tomography (PET). Chemically, it is 2-deoxy-2-[¹⁸F]fluoro-D-glucose, a glucose analog, with the positron-emitting radionuclide fluorine-18 substituted for the normal hydroxyl group at the C-2 position in the glucose molecule.

The uptake of ¹⁸F-FDG by tissues is a marker for the tissue uptake of glucose, which in turn is closely correlated with certain types of tissue metabolism. After ¹⁸F-FDG is injected into a patient, a PET scanner can form two-dimensional or three-dimensional images of the distribution of ¹⁸F-FDG within the body.

Since its development in 1976, ¹⁸F-FDG had a profound influence on research in the neurosciences. The subsequent discovery in 1980 that ¹⁸F-FDG accumulates in tumors underpins the evolution of PET as a major clinical tool in cancer diagnosis.^[3] 18F-FDG is now the standard radiotracer used for PET neuroimaging and cancer patient management.^[4]

The images can be assessed by a nuclear medicine physician or radiologist to provide diagnoses of various medical conditions.