radiopharmacologique

Radiopharmacology, sometimes referred to by the French term radiopharmacologique, is the field that studies radiopharmaceuticals—compounds labeled with radioactive isotopes used to diagnose and treat diseases. It sits at the intersection of radiochemistry, pharmacology, radiobiology, and medical physics, focusing on how radiolabeled substances interact with biological systems, how they are prepared, delivered, distributed, metabolized, and excreted, and how the radiation dose to tissues is estimated.

Diagnostic radiopharmaceuticals enable functional imaging in nuclear medicine using single-photon emission computed tomography (SPECT) or positron emission tomography (PET). Common radionuclides include technetium-99m, iodine-123, gallium-68, and fluorine-18, which allow visualization of physiological processes such as metabolism, perfusion, or receptor expression.

Therapeutic radiopharmaceuticals deliver cytotoxic radiation to diseased tissues, typically employing beta or alpha emitters such as iodine-131, lutetium-177, yttrium-90, or actinium-225. These agents are designed to accumulate in target tissues (for example tumors) to maximize tumor dose while sparing healthy tissue.

Production and regulation: radiopharmaceuticals are produced in cyclotrons or nuclear reactors and often have short half-lives, requiring dedicated radiopharmacy facilities, strict quality control, Good Manufacturing Practice (GMP), and comprehensive radiation safety and dosimetry assessments.

Applications and outlook: radiopharmacology supports oncology, cardiology, and neurology, with growing emphasis on theranostics—the paired use of diagnostic and therapeutic radiopharmaceuticals for personalized treatment. Ongoing research aims to improve targeting, optimize dosing, and expand regulatory pathways for new agents. Examples include diagnostic fluorine-18 FDG and Ga-68 DOTATATE, and therapeutic lutetium-177 DOTATATE and iodine-131.