Radioactive tracers are used in imaging tests that help find
problems inside the body. These tracers give off particles that can be detected
and turned into a picture to help find problems in organs or other
The tracer is usually given through an intravenous (IV) line
placed in a vein. But the tracer also may be given by mouth or by inhaling it into the lungs. The tracer then travels through the body and may collect in a
certain organ or area.
The types of tests that use radioactive tracers include positron
emission tomography (PET) and nuclear medicine scans to look at specific organs
such as the liver, lungs, kidneys, and gallbladder.