Fluorodeoxyglucose (FDG) is a radiopharmaceutical used in medical imaging, particularly in positron emission tomography (PET) scans. It is a glucose analog that contains a radioactive fluorine isotope, allowing it to be detected by imaging equipment. FDG is taken up by cells in the body, especially those with high metabolic activity, such as cancer cells, making it useful for diagnosing and monitoring various conditions. When injected into a patient, FDG accumulates in areas of increased glucose metabolism. This property helps healthcare professionals identify tumors, assess their size, and evaluate treatment effectiveness. The imaging process provides valuable information for oncology and other medical fields.