The Health and Medicine Track of the Third Philippine Nuclear Congress from December 7-9, 2015 discussed the safety measures for administering radioactive iodine therapy, or radioiodine, to a patient with hyperthyroidism.
“Any use of radiation on patients must be justified. You need further tests to make sure that iodine therapy is the best option,” said Eulinia M. Valdezco of the Philippine Association for Radiation Protection during the multi-sectoral forum organized by the Department of Science and Technology[ (DOST) and its attached agency, the Philippine Nuclear Research Institute (PNRI).
Radioactive iodine, which takes the form of an oral capsule, stops the overproduction of the hormone thyroxine by the thyroid gland, which characterizes hyperthyroidism. Thyroxine helps in the digestive process, brain development, heart and muscle function, and bone maintenance. Excessive amounts of the hormone leads to sudden weight loss, sweating, rapid or irregular heartbeat, and irritability.
Among the safety measures mentioned in the discussion were the medical team’s preparedness for an emergency such as when the patient is not able to swallow the capsule and expels it instead, thus spawning the possibility of contamination.
The medical team for the radioiodine treatment is composed of an authorized physician, radiation protection officer, medical physicist, and nuclear medicine technologist. Such composition will ensure the protection of the patient, hospital workers, and the patient’s own family.
Another safety measure mentioned was the practice of having the patient himself take the capsule and put it into his mouth, instead of the technologist opening the canister and giving it to the patient so he could take the capsule.
The necessity of wearing a lead gown or apron was also raised. Said lead gown should not have been used in x-ray radiology, said Valdezco, formerly the head of the nuclear regulations, licensing and safeguards division of PNRI. An x-rayed gown is not optimized protection as it provides less protection, she explained.
“In nuclear medicine, one should minister a radiopharmaceutical to the patient. The source of exposure to radiation is now the patient. Our concern is the safety of the people around the patient – whether it is the workers in the hospital, the doctors who are doing the procedure, the family members once the patient is released from the hospital, and the general public that he encounters in the course of his work,” Valdezco said.
The cells of the thyroid gland are the main cells that can take in iodine. Thus, the other cells in the body are not heavily affected by radiation exposure. Upon absorption of radiation, the thyroid cells shrink and then get destroyed.
There are other treatments available for hyperthyroidism, namely anti-thyroid medication and surgery. Radioactive iodine is the most common treatment in the US.