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Radioisotope therapy

What is radioisotope therapy?

Radioisotope therapy uses radioactive medicines to treat some types of cancer. You have the radioisotope as a drink, capsule or injection.

How does radioisotope therapy work?

The radioisotope travels around your body in the bloodstream to the area where the cancer is. The radioactive part is called an isotope. It may be attached to another substance, which is designed to take the isotope to the cancer.

The cancer cells take up the radioisotope and get a high dose of radiation, which destroys them. The healthy cells receive a low dose or no radiation. So usually this treatment causes few side effects.

Your doctor will tell you how you will have your treatment and what the possible side effects are.

Types of radioisotopes

There are different types of radioisotopes. Each type may treat a different type of cancer. The radioisotopes most often used to treat cancer are:

  • iodine-131 – for thyroid cancer

  • radium-223 – for cancer that has spread to the bones (secondary bone cancer)

When radioactive iodine (iodine-131) is attached to another chemical called MIBG it can help diagnose and treat some other types of cancer. Such as neuroendocrine tumours.

Read about the different types of radioisotope therapy

Radiation safety

You may need to follow some safety procedures when you have treatment with radioisotopes. This is to help protect others from being exposed to the radiation. You may stay in a single room in the hospital while you have treatment. And you may need to limit visitors during this time.

When you go home you may need to follow certain precautions to protect your family and friends. This is often only for the first few days you are at home.

The safety precautions you need to take will depend on the type of treatment you are having. Your treatment team will explain what these precautions are and how long you need to follow them for.

Spills

When you have radioisotope therapy, the radioactivity goes all around your body. This makes your saliva, sweat, blood and urine all radioactive.

Your treatment team will give you instructions on how to safely clean up any fluids that may spill. And may tell you to flush the toilet twice after using it. You may need to avoid contact with children and pregnant women for a time.

Coping with isolation

The radiation safety measures can add to the worries you might already have about your treatment. But it’s important to follow them as it is to keep you, your treatment team, and your friends and family safe.

You may be worried about feeling lonely if you need to stay in hospital in a single room for your treatment. It can help to talk to your nurses about your worries. They can reassure you.

You will still be able to call the nurses if you need anything. They will just need to limit the time they are with you so they are not exposed to too much radiation.

You might be able to take in some personal items, such as books or magazines, to help fill your time. After radioisotope therapy, these items might become contaminated with radioactivity from your sweat. So they may suggest not bringing too many items in and nothing of value. The room will have a television and a phone.

The nurses or radiographers will tell you what you can or can’t bring in.

For more detailed information about the safety precautions for internal radiotherapy go to the treatment section of your cancer type.

Go to your cancer type

Last reviewed: 07 Jun 2024

Next review due: 07 Jun 2027

Types of radioisotope therapy

Radioisotope therapy uses radioactive medicines to treat some types of cancer. It is also known as radionuclide therapy. You have the radioisotope as a drink, capsule or injection.

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