Iododeoxyuridine

5-Iododeoxyuridine is a nucleoside and a thymidine analogue abbreviated IUdR. IUdR is a radiosensitizer and increases the amount of DNA damage received from ionizing radiation. The compound is quickly removed from the DNA in normal cells through DNA mismatch repair but it can accumalate in mismatch repair deficient cells such as certain types of cancer cells and increase the amount of DNA damage induced by ionizing radiation therapy therefore increasing the effectivess of the therapy.