This therapy uses radiopharmaceuticals - radioactive elements combined with a drug or naturally occurring agent - that deliver therapeutic doses of radiation.
This is an option for some benign diseases such as generally overactive thyroid disease and some types of cancers - commonly thyroid cancers and some types of breast and prostate cancers.
Some patients can be treated as outpatients. Those requiring higher doses of radiation may require admission until their radiation levels have fallen to safe levels. This usually involves a short admission of three to four days to the Rathgar centre (see Radioiodine Information Booklet).