Fludeoxyglucose (18F) Advanced Drug Monograph

Fludeoxyglucose (18F) Report

Name: Fludeoxyglucose (18F) Name (English): Fludeoxyglucose (18F) DrugBank ID: DB09502 Type: Small Molecule CAS Number: 63503-12-8

Fludeoxyglucose (18F), also known as 18F-FDG, is a radioactive tracer used in positron emission tomography (PET) imaging. It is an analog of glucose, where the hydroxyl group at the C-2 position is replaced by a fluorine-18 atom.

Indications: 18F-FDG is used in PET scans to visualize glucose metabolism in the body. Clinically, it is primarily used in:

• Oncology: Detection, staging, and monitoring of various cancers. Cancer cells typically have higher glucose uptake than normal cells.
• Cardiology: Assessment of myocardial viability in patients with coronary artery disease. Viable myocardium exhibits glucose metabolism.
• Neurology: Evaluation of brain glucose metabolism in conditions such as epilepsy, Alzheimer's disease, and brain tumors.

Pharmacodynamics: 18F-FDG is transported into cells by glucose transporters and is phosphorylated by hexokinase to 18F-FDG-6-phosphate. Unlike glucose-6-phosphate, 18F-FDG-6-phosphate cannot be further metabolized and is trapped within the cell. The accumulation of 18F-FDG-6-phosphate reflects the rate of glucose uptake and phosphorylation in tissues.

Pharmacokinetics: Following intravenous administration, 18F-FDG is rapidly distributed throughout the body. It is cleared from most tissues within 24 hours, primarily through urinary excretion.

Adverse Effects: No FDG-specific adverse events have been commonly reported. Reactions are typically related to the injection procedure or potential allergic reactions to other components in the formulation.

Interactions: Medications that affect blood glucose levels, such as corticosteroids, insulin, and antidiabetic agents, can influence 18F-FDG uptake and image interpretation. Colony-stimulating factors can also increase 18F-FDG uptake in the bone marrow.

Dosage and Administration: The dose of 18F-FDG administered varies depending on the imaging procedure and the patient's weight. It is administered intravenously by trained personnel in a nuclear medicine facility.

Contraindications: There are generally no absolute contraindications for 18F-FDG administration. However, relative contraindications may include uncontrolled hyperglycemia or recent administration of glucose-containing solutions.

Precautions: Adequate hydration is recommended to enhance urinary excretion of the radiotracer. Patients with diabetes mellitus should have their blood glucose levels controlled before the procedure. Pregnancy and breastfeeding should be considered, and alternative imaging modalities may be preferred in these situations unless the benefit outweighs the risk.

Storage: 18F-FDG should be stored according to the manufacturer's instructions, typically at room temperature and away from direct light. It has a short half-life (approximately 110 minutes), so it must be used within a limited time frame after production.