Radioiodine (I-131) treatment of benign thyroid diseases
Radioiodine I-131 is widely used to treat the following benign thyroid conditions: hyperthyroidism in Graves-Basedow disease, the multinodular toxic goiter, autonomous thyroid nodules as well as the large euthyroid goiter.
Purpose of the treatment is to cure hyperthyroidism or shrink the enlarged thyroid gland. Radioiodine is supplied for oral administration in pre-made capsules. The nuclear medicine specialist determines the I-131 therapeutic dose for each patient individually – depending on the disease, volume of the thyroid (or autonomous nodules) and thyroid uptake. Usually, a single I-131 dose is successful in treating hyperthyroidism. However, should the second treatment be needed, the minimum 6 months’ interval between the radioiodine therapies is required.
Indications for the treatment:
- Graves-Basedow disease
- multinodular toxic goiter
- autonomous thyroid nodules
- large euthyroid goiter
pregnancy and breastfeeding (up to 6 weeks from the termination). Women of reproductive age must exclude pregnancy before the treatment.
It is recommended to run a pregnancy test 3 days before the radioiodine treatment. The test is not necessary if the patient’s medical record contains unambiguous data excluding possible pregnancy, and the patient makes a written statement of being not pregnant.
The patient should use anticonception for at least 4 months after I-131 treatment.
Patient eligibility for the treatment:
Each patient must be assessed for eligibility before undergoing any isotopic treatment procedure. Please bring your recent medical records to the eligibility assessment visit with you: thyroid blood test results (TSH and FT4), thyroid ultrasound results, and in case of multinodular toxic goiter – also thyroid biopsy results. Shortly before the visit, the patient undergoes thyroid scintigraphy and is then interviewed and examined by the nuclear medicine specialist. Based on the patient’s anamnesis, physical examination and available imaging records, the doctor determines the individual radioactivity dose to be administered. During the eligibility assessment visit, the patient should provide the doctor with the important information on the previous treatment and imaging procedures with iodinated contrast media (e.g. computed tomography with iodine-based contrast agents) and/or iodine-rich medication taken (e.g. amiodarone).
If you would like to schedule an appointment for the eligibility assessment, you can do it in person, by mail or by phone.
Patient preparation for the treatment:
- anti-thyroid drugs (Metizol, Propycil, Thyrozol) should be stopped 5 days before the treatment, unless your nuclear medicine doctor advises otherwise
- stop taking iodine-containing medicines 2-3 months before the treatment (check your multivitamin supplements, eye drops for iodine)
- other medication can be taken as usual, provided it contains no iodine
- abstain from food for 3-4 h before swallowing the I-131 capsule
How is the treatment performed?
- The patient swallows the radioactive iodine capsule (with some water) at Nukleomed in the presence of the doctor.
What do I need to do after the treatment?
- abstain from food for 1 hour after swallowing the radioiodine capsule
- increase your fluid intake for the first 4 days after the treatment to speed up elimination of the isotope that was not taken up by the thyroid
- take medication after the isotopic treatment strictly according to the recommendations of your nuclear medicine doctor (types and doses to be taken are determined at the consultation)
- sleep in a separate room for 7-14 days
- minimize staying in the same room with other family members, keep several meters distance from children and pregnant women for 4-6 weeks from treatment
- launder your linens and clothes separately for about 4 weeks
- attend follow-up appointments at the time recommended by your doctor
Any type of treatment (including pharmacological and surgical) can be administered after the radioiodine therapy.
The only permanent side effect of the radioiodine treatment can be hypothyroidism.