Systemic radiation therapy

Systemic radiation uses radioactive drugs to treat certain types of cancer. These drugs can be given by mouth or put into a vein; they then travel throughout the body.

What is systemic radiation therapy?

Radioactive drugs called radiopharmaceuticals- are used to give systemic radiation. These radiation sources are in the form of a liquid made up of a radioactive substance, which is sometimes bound to a special antibody (called a monoclonal antibody  that attaches to the cancer cells. Radioactive iodine, strontium, samarium, and radium are some other types of systemic radiation used to treat certain types of cancers, such as thyroid, bone, and prostate cancers.

The radiopharmaceuticals may be given in a vein (IV) or taken by mouth. They travel in the blood throughout the body. They collect where the cancer is to give off their radiation and kill the cancer cells.

The radiopharmaceuticals are kept in special containers that hold the radiation inside so it can’t affect others. You’ll likely be treated in a shielded room that also contains the radiation. The health professionals handling the drugs may wear safety gear that protects them from exposure while they’re giving you the radioactive drug.

Will I be radioactive during or after systemic radiation treatment?

Because systemic radiation uses an unsealed radioactive substance that goes through your whole body, some radiation will be in your body for a few days until your body has had a chance to get rid of it. You may need to stay in the hospital for 1 or 2 days.

Your cancer care team will tell you what precautions to take until your body no longer contains radiation that might affect others. These precautions vary depending on the substance used.

Patient and family safety

Sometimes certain safety measures are needed to protect the people around you from the systemic radiation in your body. This is because the radioactive materials can leave your body through saliva, sweat, blood, and urine, making these fluids radioactive.

In most cases, the safety precautions must be followed only the first few days after treatment. Over time, the radiation becomes weaker and your body gets rid of it. Talk to your cancer care team about how long this may take in your case, and if there are special precautions you will need to take.

You might be told to follow these precautions for a certain amount of time:

  • Flush the toilet twice after each use, and wash your hands well after using the toilet.
  • Use separate utensils and towels (laundry may need to be washed separately).
  • Drink extra fluids to flush the radioactive material out of your body.
  • No kissing or sexual contact (often for at least a week).
  • Keep a distance of one arm’s length between yourself and any others who spend more than 2 hours next to you in any 24-hour period. (You may need to sleep alone for a week or so.)
  • Limit your contact with infants, children, and women who are pregnant.
  • Limit your contact with pets.

Ask your cancer care team about the precautions you need to take. Be sure you understand what you need to do to protect the people around you.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: June 30, 2015 Last Revised: June 30, 2015

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