Radio-iodine treatment procedure in case of thyroid cancer

The primary management for patients with thyroid cancer is surgical removal of the thyroid. Radioiodine therapy is used after the thyroid has been removed.

The goal of postoperative radioiodine therapy is to destroy residual thyroid tissue and metastases in differentiated thyroid cancer. The dose of radioiodine required for treatment is individual and depends on the type and extent of the disease.

There are two ways to prepare for radioiodine therapy:

  • Thyroid hormone (L-Thyroxin) is withdrawn 4 weeks before the planned radioiodine therapy.
  • Thyroid hormone (L-Thyroxin) is not withdrawn and thyrotropin (Thyrogen®) is injected intramuscularly on two consecutive days before the radioiodine therapy.


You should follow a low-iodine diet for two weeks before you start your treatment.

You should not eat for 4 hours before taking the radioiodine capsule. You may drink water. After administering the capsule, you will be isolated for at least two days in a special radiation-shielded single-bed treatment ward where you can use a shower and toilet, TV, radio, fridge, kettle, Wi-Fi, etc.

48-72 hours following administration of the radioiodine capsule, you will have a whole-body scan with a gamma camera.

On the day you leave the hospital, the radiation level in your body will be measured. According to the measurement result, post-therapy radiation safety requirements will apply to you when interacting with other people, which will be introduced to you by the hospital staff. The radiation safety requirements are also given to you in writing (‘Radiation safety requirements for patients receiving radioisotope therapy’).