Radioiodine Therapy Thyroid Cancer
What is radioiodine therapy?
Radioiodine is a radioactive form of iodine. It is used to treat thyroid diseases like thyrotoxicosis (an overactive thyroid gland). It is also used to treat some forms of thyroid cancer.
Iodine is needed for the normal working of the thyroid gland. It is part of everyone's diet and is taken up into the gland. Radioiodine is taken up by the thyroid cells and the radioactivity destroys them. The treatment is painless.
How is radioiodine given?
Radioiodine is usually given by mouth as a capsule, washed down with water. If needed you could be given an anti‑sickness tablet before treatment, although most people don't feel sick during or after therapy. If you can not swallow a capsule, please let the department know as soon as possible.
Is radioactive iodine safe?
Radioiodine has been used to treat thyroid diseases for over 40 years. It is both safe and effective.
This treatment is being given to benefit you. However, there is a possibility that it could be harmful to others. To reduce any risks you will be asked to take care with your personal hygiene and to observe certain precautions (see safeguards).
Are there any side effects?
Radioiodine therapy may cause tiredness and occasionally, nausea. There may be slight swelling or discomfort in the neck but this is rare. Your taste may also be affected in the short term.
Women are advised not to become pregnant and men should not father any children in the year following treatment.
Do I have to come into hospital?
Yes, you will probably need to stay in hospital for three to six days. How soon you can go home depends on how quickly the radioactivity leaves your body.
How long do I have to stay in hospital?
You can go home when a safe level of radioactivity has been reached. The safe level is based on your individual circumstances, for example if you live with babies or young children.
The physicist is trained in the handling of radioactive substances and all aspects of safety. S/he will explain your treatment and take daily measurements of radioactivity. The physicist will also discuss your return home, your work and your social activities and will advise you. If you have any concerns or questions, please ask.
Before radioiodine therapy. What may I eat?
A diet which is rich in iodine can reduce the effectiveness of the treatment, so we offer the following suggestions:
Do eat
- fresh meat
- vegetables
- fresh fruit
- pasta
- rice
(which are low in iodine)
Do not eat
- foods artificially coloured pink or red such as:
- canned and glace cherries
- canned strawberries
- spam
- salami
- certain pastries and sweets
for three weeks before coming into hospital. This is because they may contain the colouring material E127, which is rich in iodine. Foods coloured by spices rather than dyes are allowed.
Do not take
- cough medicine
- iodised table salt
- sea salt
- vitamin supplements including cod-liver oil
- mineral supplements
for three weeks before coming into hospital. Many of these contain iodine.
Cut down on
- fish and seafood
- dairy produce such as:
- eggs
- cheese
- milk
- milk products
for three weeks before coming into hospital. These all contain some iodine.
What about my tablets?
Thyroid hormone tablets interfere with radioiodine therapy. You will be asked to stop taking these for a time before and during treatment. Do not take any of these tablets from the given date until you are advised to restart.
You may feel weak or tired when you're not taking your tablets. This is normal and will disappear once you start taking them again. This is usually a few days after you have had your radioiodine.
When you come into hospital please bring any other tablets or medicines with you and show them to the doctor. You should be able to continue taking them, unless they are vitamin or mineral supplements.
Four weeks before admission:
Stop taking T4 or Thyroxine tablets
Start to reduce the amount of iodine in
your diet by following the advice above.
Stop taking vitamin or mineral supplements and cod liver oil
Two weeks before admission:
Stop taking T3 or liothyronine (Tertroxin) tablets.
What should I bring into hospital with me?
When choosing what to bring into hospital, for example a personal music player, remember that you may need to leave some things behind if they carry traces of radioactivity after your treatment. You will be able to collect them later.
Don't bring large amounts of money, or valuables, into hospital. Give this
to the ward clerk before your treatment.
The following list may also be useful:
- Items for your personal hygiene
- lemon drops or other mouth-watering sweets
- fruit
- biscuits
- fruit squash or other drinks
- enough books, magazines, knitting, games, etc. to last your stay
- The room has a television and video, radio and a telephone. You may be able to borrow video films.
What happens when I come into hospital?
When you come into hospital you will be cared for in a single room with
an en suite bathroom. During treatment the staff won't be able to spend
very long with you but they will come in to attend to your needs.
You will be able to call the staff, using a call button, if you need them.
May I have visitors?
Yes, but all visitors must stay behind a special screen to protect them against radiation, and there may be a time limit on the length of their visit. Children under 16 years old and pregnant women must not visit you. They are particularly prone to the effects of radiation. You must not have any physical contact with your visitors. You must not hand them anything, such as food, drink, magazines or clothing.
When will I have my treatment?
You will be given your radioiodine as soon as any tests have been completed and you have seen the doctor and physicist.
You must have nothing to eat or drink for one hour before your treatment and for two hour afterwards. You may have sips of water if you are thirsty.
What safeguards are taken concerning radioactivity?
After you have received your treatment all your body fluids, such as saliva, sweat, blood, urine and stools, will be slightly radioactive. Some of this radioactivity may get onto clothing, bed linen and other items.
The hospital will provide you with the following:
- night clothes
- dressing gown
- towels
- tissues
- Your meals will be served on paper plates with disposable cutlery and plastic cups.
What can I do to help?
There is a lot you can do to prevent the spread of radioactivity and also increase the speed with which radioiodine leaves your body.
- Drink extra fluid, up to twice as much as usual.
- Suck lemon drops or other sweets which make your mouth water. This reduces the build up of radioiodine in your saliva.
- Shower daily or more often if you wish.
- Don't splash water outside the washbasin when washing and particularly when cleaning your teeth. Rinse your washcloth and toothbrush well.
- Flush the toilet twice after use. Take care not to splash urine outside the pan (men may find this easier if they sit down).
- Tell the nurses straightaway if you have an accident with spillage or splashing.
- Tell the nurses if you become constipated so you can receive a laxative. (It is important that you have your bowels open regularly).
- Use tissues and flush them down the toilet.
- Wash your hands before reading, knitting or handling items a great deal.
- Don't give anything from your room to anyone.
- If you are concerned about anything or have questions, please ask the staff caring for you.
What tests will I have after my treatment?
Once or twice a day the physicist will measure the radioactivity in your body. This only takes a few minutes.
When the radioactivity has fallen to a safe level you will be allowed to leave the hospital.
You will have to come back for a scan in the Nuclear Medicine Department. The date for this scan will be decided by the time you leave the hospital. We try to do the scan before you leave the hospital, but you may have to wait for a couple of days before you can have this scan.
Will I have to come back for another treatment?
Possibly; some people may need two or more treatments. Your hospital doctor will discuss your case with you when you return to the outpatient clinic. Your appointment will be about two months after your radioiodine therapy.
Where can I get more information and help?
If you have any queries about your illness or treatment or experience
any unexpected problems, please contact:
Your hospital doctor (Consultant),
or one of his/her team,
or nuclear medicine physicist.
Further Information
cancerBACUP
3 Bath Place
Rivington Street
London EC2A 3JR
Tel: (020) 7 613 2121
Society on Nuclear Medicine
European Association of Nuclear Medicine
References
This information has been produced by:
Head of Department: Mr L Jansson
Date Produced: February 2007
Review Date: February 2008
Responsible Clinician: Dr RP Crellin, Consultant Oncologist
