What are radiopharmaceuticals?

Radiopharmaceuticals are specialized drugs that contain radioactive isotopes. These compounds are specifically designed for use in nuclear medicine, where they can be employed for both diagnostic and therapeutic purposes. The radioactive isotopes emit radiation, which can be detected and used to create images of the body's internal structures and functions, allowing healthcare professionals to assess conditions such as cancers, infections, or other diseases.

The unique characteristic of radiopharmaceuticals is that they target specific organs or cellular receptors, allowing for the delivery of radioactive material precisely where it is needed in the body. This targeted approach maximizes the utility of the radioactive emissions for imaging or treatment, making them crucial in diagnostic processes like PET scans and therapeutic applications such as radioimmunotherapy.

The other options imply substances that do not contain radioactive isotopes or suggest uses that deviate from the fundamental principle of radiopharmaceuticals in nuclear medicine. Therefore, the definition of radiopharmaceuticals as drugs that contain radioactive isotopes accurately encapsulates their purpose and application in the medical field.