Radioactive Iodine in Thyroid Cancer

If it has been determined that you may receive radioactive iodine treatment for thyroid cancer without being hospitalized, the state of Texas does not require informed consent for radioactive iodine treatment, but we obtain your consent because it is important that you understand why you are being treated. This document can inform you of what to expect from treatment and how to follow simple precautions after treatment. Read more about our radioactive iodine clinic.

The type of thyroid cancer that you have is a well-differentiated type. The cells in this type of thyroid cancer are expected to concentrate iodine just as normal thyroid cells do. Other cells in the body do not concentrate iodine. Both normal thyroid cells and thyroid cancer cells will be inactivated or destroyed by the radioactive iodine treatment. Other cells in your body receive some radiation but they are not damaged as thyroid cells are because they do not concentrate iodine.

Radioactive iodine treatment involves taking some capsules that contain radioactive iodine. There may be several capsules but all of them will be taken while you are here and within a short period of time. These capsules contain a small amount of iodine but it is radioactive iodine. This will not make you feel ill. We will observe you for about 30 minutes and then you will be able to leave. You will be fine to drive and to work. This medication does not make you feel differently. It does not cause sleepiness, headaches or nausea. If you drove a car today, you will be fine to drive home.

Most patients have no side effects from the radioactive iodine. Some patients will have swelling of the salivary glands at the sides of the face and below the chin. It may be mildly painful. This may be treated with ibuprofen such as Advil of Motrin. We recommend that you take two 200 mg tablets four times per day if you have this discomfort. If you are unable to take ibuprofen, we will discuss an alternative with you.

You may start taking thyroid hormone replacement at 48 hours (two days) after this treatment. If you have already been on thyroid hormone replacement, such as Levoxyl or Synthroid, you will resume taking the same dose. If you have a prescription from your referring physician, then you will need to take the dose prescribed. If you do not any thyroid hormone replacement, we will discuss this with you and make a plan.

Precautions to follow after administration of the radioactive iodine are simple. There will be a small amount of radiation coming from you. 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. This is because it takes several weeks for all of the radioactive iodine to be eliminated from your body. We recommend that you keep a distance of 5-6 feet from other persons for the first two days after treatment for as much of the time as is reasonably possible. You should keep a distance of 3-5 feet from other persons on the third day through the seventh day after treatment. This precaution is no longer necessary after one week.

The second precaution to follow is to not let others have contact with your bodily secretions. This includes saliva, sweat, urine, stool, semen and vaginal secretions. You should not have sexual relations for one week after treatment. Also, take care that others are not using your bath towel or eating or drinking with your tableware or utensils. Kissing should be limited such that others do not have contact with your saliva. You may cook for your family if you take care to wash your hands carefully before handling food. We recommend that the bathroom sink and toilet be rinsed well after use. Two flushes of the commode are sufficient. You do not need to follow this precaution after one week from the time of treatment.

If you need to travel by airplane or commercial vehicle that may be subject to security inspection, you should have your copy of this form with you. The radioactive iodine may be detected for as long as three months after treatment. This is because the detectors used by security personnel are set to detect minute amounts of radioactive materials. This does not mean that you need to follow precautions as described above. The recommended one-week of precautions is sufficient. If security personnel notify you that you have not passed screening, inform them that you have received treatment with a radioactive material. You are not required to inform them ahead of time. Most screenings will not detect the very low level of radiation that may be present during the three months after treatment.

WOMEN: It is important that you are not pregnant or nursing at the time of treatment. Also, if you have been nursing an infant at any time in the previous six months, please inform us of that. We recommend that you not become pregnant for at least six months after treatment.

MEN: Sperm count may be decreased for several weeks after treatment and then return to normal. You will not know if your sperm count is decreased or not so methods to prevent pregnancy should be used just as you would normally use. If we are treating you with an unusually high dose of radioactive iodine, we will discuss fertility issues with you.