Will cancer treatment make me radioactive?
One form of treatment for cancer is a high-dose x-ray called radiotherapy. During radiotherapy an X-ray is aimed at the area where there are cancer cells.
The X-ray then exits the body, and you are safe to interact with people without exposing them to radiation. You are therefore not radioactive after radiotherapy.
Another type of cancer treatment is called radioisotope therapy, with the most common being radioactive iodine for the treatment of thyroid cancer. This is an injection into your bloodstream and the treatment stays in your body for longer, making you radioactive for a few days.
During that time, you should avoid being in contact with young children and pregnant women, and if you share toilet facilities with others, you’ll need to flush the toilet twice each time you go for the first 48 hours. This is because your urine will also be radioactive.
There are some cancer scans (not treatments) which also make you radioactive for 24-48 hours, because you need to have a radioactive injection immediately before your scan. Examples include bone scans, PET scans and some heart scans. The same precautions apply in terms of avoiding contact with vulnerable people and sharing toilet facilities.
