What is an FDG radiotracer used for?

FDG is a glucose-like substance linked to a small radioactive signal. After it is given, commonly through a vein, tissues that use more glucose may take up more FDG. A PET scanner detects the signal, while the CT part shows the body’s anatomy. Together, the images help the team locate and assess areas of activity.

In oncology, FDG imaging may help investigate a suspected cancer, assess the extent of disease, plan treatment, or evaluate a response. Increased uptake is not specific to cancer; infection, inflammation, healing, and normal activity can also affect the scan.

The imaging centre will give instructions about fasting, drinking water, medicines, and activity before the appointment. Tell the team if you have diabetes, are pregnant or may be pregnant, are breastfeeding, or have difficulty staying still. Avoid strenuous activity if instructed, because muscle activity can influence the images.

After the injection, you usually rest quietly while the tracer travels through the body. During scanning, remain still and follow breathing or positioning instructions. Drinking water afterward may be advised to help clear the tracer; follow the centre’s specific guidance about contact with others.

Tell staff immediately about trouble breathing, facial swelling, dizziness, or severe discomfort after the injection. Contact your care team after leaving if you develop persistent swelling or pain at the injection site, feel faint, or cannot keep fluids down. Seek emergency care for severe breathing difficulty or loss of consciousness.

Ask what the scan is intended to answer, how to manage diabetes medicines and fasting, whether your medicines affect preparation, when results will be available, and which findings might require another test.