Radioactive Iodine for Hyperthyroidism

General information about radioactive iodine

The Texas Medical Disclosure Panel has not established and does not require disclosure of specific risks and benefits associated with Radioactive Iodine Treatment of Hyperthyroidism. We provide the following to you in order that you may make an informed decision about receiving this treatment.

Hyperthyroidism is the overproduction of thyroid hormone by the thyroid gland. It is relatively common problem and usually has no specific cause. Hyperthyroidism can be treated with anti-thyroid medication that is taken one to several times daily until thyroid function either improves or the thyroid becomes less effective at producing thyroid hormone. Hyperthyroidism lasts only a few months in some patients but in the majority of patients with the same condition for which you are being treated, the thyroid continues to overfunction for several months to many years. An alternative to anti-thyroid medication is treatment with radioactive iodine. Radioactive iodine is given as a single dose. It is a capsule that is taken by mouth. It does not make you feel ill in any way. It does not make you drowsy; you will be fine to drive home after receiving this treatment. It takes 6-10 weeks to be certain that you have had an adequate response to treatment, however, most patients report feeling better within 2-3 weeks.

The side effects of this treatment may be minimal or none at all. Occasionally, patients experience some soreness in the neck region that lasts one to several days. This will respond to treatment with ibuprofen (Motrin or Advil). Rarely, patients experience an increase in symptoms of hyperthyroidism during the week following treatment; if you have marked worsening of symptoms you should call your physician so that he/she may prescribe a brief course of anti-thyroid medication.

The expected outcome of this treatment is to decrease thyroid function to below normal levels, that is, to make you hypothyroid. The radioactive iodine does this by damaging the thyroid cells’ ability to make thyroid hormone. When you become hypothyroid, your physician will start you on thyroid hormone replacement. This is a pill of pure thyroid hormone, just like the thyroid hormone that your thyroid makes. You will take thyroid hormone replacement for the rest of your life. It is a one pill taken every day. The advantage of becoming hypothyroid is that you will not be at risk of becoming hyperthyroid again. This is important because of the deleterious effects of hyperthyroidism, particularly the effects on your heart. Only a small percentage of patients will not have an adequate response to treatment resulting in persistence or recurrence of hyperthyroidism. A second treatment with radioactive iodine may need to be given to those few patients.

It is important that you are not pregnant at the time this treatment is given as the radioactive iodine could seriously affect the baby’s growth and development. You must provide information to us to be certain that you are not pregnant. If you are not certain, we will do a pregnancy test before treating you. Also, it is necessary that patients not breast feed an infant for the month following this treatment.

Precautions should be taken for 72 hours (3 days) following treatment to reduce radiation exposure to other persons. These precautions are simple. Be certain that other persons have minimal connect with you bodily secretions, particularly your saliva and urine. Take care that others do not share your towel, eating utensils and drinks during these 3 days. Do not have sexual relations during these 3 days and sleep alone for these 3 days.

Hyperthyroid treatment outpatient instructions: precautions after iodine treatment

Although only a small amount of radioactivity is involved with this treatment, it is still important to follow these simple precautions in order to minimize radiation exposure to your family members and friends. Since the radioactivity is excreted through all bodily fluids, mainly urine, as well as feces, sweat and saliva, it is essential to isolate these fluids. After you've had your radioactive I-131 scan/treatment, you should:

1) A separate bathroom which only the patient uses is required for 3 days after treatment. This will prevent radioactivity exposure to others. You may not go to a hotel as this will expose hotel staff and other hotel guests to radioactivity.

2) Always wash your hands with soap and water after you use the bathroom. Dry your hands thoroughly with a towel that only you are using. Separate all towels, washcloths, and bed linens. Wash all of these items separate from the family wash.

3) In order to dilute the amount of radiation in urine and feces, always flush the toilet at least two or three times after using the bathroom.

4) Separate your plates, silverware and drinking cups. Better yet, use paper plates and plastic cutlery, so you won't have to wash your dishes separately from the rest of the family.

5) If you are cooking for the family, remember not to taste any of the food with a spoon that will be used for food preparation. Once it touches the saliva in your mouth it is considered to be contaminated and must be washed separately.

6) Sleep in a separate bed from your partner. Avoid open mouth kissing and all sexual contact.

7) Radiation exposure is directly related to the amount of time you spend with another person as well as how intimate and close your contact is with them. Avoid prolonged intimate physical contact with babies, children and pregnant women. You may perform all essential duties such as changing diapers, if no one else is available to help you. Wash your hands before and after these tasks.

8) In order to flush out the radiation faster, keep yourself well hydrated (preferably with water) so that the radioactive iodine will be passed out of your body through your urine.

These precautions should be followed for three days after the I131 test. After this period of time, the radiation exposure to other people is negligible and you do not need to follow any additional precautions.

If you have small children in the household, the following precautions are necessary:

1. For the first 3 days after treatment, avoid contact with children as much is possible. Have someone carry out child care such as feeding, dressing, changing and bathing. Do not carry or hold your child for more than 10 minutes per day for these 3 days. Do not sleep with your child. Do not ride in a car with your child.

2. After 3 days, you may have some close contact with your child. For 2 weeks, limit time spent holding or carrying your child to 20 minutes per day. Do not spend more than 1 hour per day at less than one arm length from your child. This should give you sufficient time to feed your child, dress your child, change diapers and bathe your child. This is in addition to the time that you can hold or carry your child. Limit riding in a car with your child to less than 30 minutes per day.