Nuclear Medicine is a medical specialty that allows modern diagnostics and treatments cancer using radiopharmaceuticals original radiotracers (drugs linked to a radioactive isotope). Radiopharmaceuticals are considered a special group of drugs and thus their preparation and use are regulated by a set of policies that have been adopted by individual member of countries. The radiopharmaceuticals used in diagnostic examinations are administered in very small doses. So, in general, they have no pharmacological action, side effects or serious adverse reactions. In contrast, nuclear medicine procedures use a radioactive material, called a radiopharmaceutical or radiotracer, which is injected into the bloodstream, swallowed or inhaled as a gas. This radioactive material accumulates in the organ or area of your body being examined, where it gives off a small amount of energy in the form of gamma rays. Special cameras detect this energy, and with the help of a computer, create pictures offering details on both the structure and function of organs and tissues in your body.