Answer to Question #8271 Submitted to "Ask the Experts"

Category: Nuclear Medicine Patient Issues — Therapeutic Nuclear Medicine

The following question was answered by an expert in the appropriate field:

Our daughter had a thyroidectomy four weeks ago because she has follicular cancer. She will begin treatment with iodine-131 in three days—totally as an outpatient. Because she has small children, she will be staying with us. We have a private bedroom and bathroom for her to use during her stay. After the first 48 hours, she can spend limited time with us at a distance.  

Will there be any radioactivity remaining in the mattress and pillows, carpeting, and chairs that she will be using? This guest room is also used by our very young grandchildren when they come to visit. Will the items in that room retain any radiation?


The iodine will come out of your daughter's pores in sweat, urine, and stools. Frequent hand washing will reduce the spread of contamination. The bedsheets and pillowcases will retain most of the radioactive iodine, as will anything she touches, such as the phone. If we keep a patient in the hospital, we cover the TV clicker and the telephone with Saran Wrap. After the first four days the wrap can be thrown in the trash. 

She should have received written instructions on handling of the linens and bath towels. The iodine-131 will wash out in the laundry. Vacuuming will pick up hair that is shed, which will have small amounts of radioactivity in it since our heads also sweat. The conservative approach would be to cover the chair with a sheet. My institution recommends the following:

The First Four Days:

1. Most of the radioiodine in your body will come out through the urine and stool. A small portion of radioactivity will be found in your saliva and sweat. To decrease the spread of radioactivity:

  • If possible, use a separate bathroom. 
  • Flush the toilet two times after each use. 
  • Men should sit down when urinating. 
  • If urine should be spilled/splashed, wash and rinse the affected area three times, using paper towels or tissue.
  • Be sure to carefully wash your hands after using the bathroom.
  • Do not share utensils or food with others. (For example, do not drink from the same glass or share a sandwich with someone.)
  • Use towels and washcloths only you will touch.
  • Wash out the sink with a lot of water after brushing your teeth or shaving.
  • Nausea following therapy is very rare. However, if you feel sick to your stomach, try to vomit into the toilet or a plastic bag that can be sealed and thrown away. If necessary, wash and rinse any spill areas three times, using paper towel/tissue.  

2. To decrease the radiation dose to others:        

  • You should sleep in a separate bed. Cover the pillow with two pillowcases or a water-resistant cover if possible.
  • Remain in your home for the first four days.
  • Do not hold young children or spend much time near a pregnant woman.
  • Family members should stay about six feet or more from you. After the first two days, they may be closer for brief periods, such as a few minutes.
  • At the end of four days wash your laundry, including the pillowcases, by itself. This need only be done once.

If you follow these instructions, you do not have to be concerned about radiation exposure. 

Marcia Hartman, MS

Answer posted on 30 April 2009. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.