Radiopharmaceuticals are special drugs that contain radioactive materials. They are used primarily in medical imaging and treatment. When injected or ingested, these substances emit radiation that can be detected by imaging devices, helping doctors see inside the body and diagnose conditions like cancer or heart disease. In addition to diagnosis, radiopharmaceuticals can also be used for therapy. For example, certain types can target and destroy cancer cells while minimizing damage to surrounding healthy tissue. This targeted approach makes them valuable tools in modern medicine, particularly in the fields of nuclear medicine and oncology.