Radio- Iodine Therapy for Thyrotoxicosis

 What does the thyroid do?
The thyroid is a gland which produces a hormone called thyroxine.  Thyroxine has a key role to play in many
metabolic processes.  It regulates the rate at which you
release energy from the body’s stores.

What is Thyrotoxicosis?
The Thyroid gland lies in your neck and is importantly involved in a number of functions of your body. You have been referred because your thyroid is overactive and one of the ways in which this can be treated is with radio-iodine.

What is Radio- Iodine?
Iodine is a natural part of your diet and iodine in your food concentrates in your thyroid gland. Radio-Iodine is a radioactive form of iodine which gives off radiation and we can use this in carefully controlled doses to treat an overactive thyroid gland.

How Does Radio-Iodine Work?
Your symptoms are caused by your overactive thyroid gland. This gland uses iodine to make thyroid hormones, used by your body in a variety of functions.
When the thyroid is overactive it  produces too much thyroid hormone. The radio-iodine you will be given concentrates in your thyroid gland. The radiation from it will reduce the activity of the thyroid and so will improve your symptoms.
There are alternatives to radio-iodine treatment. These are:
 Continuation of your drug treatment
 Surgery to remove part of your thyroid gland
Your doctor will have discussed these options with you and you should nderstand the reasons for choosing radio-iodine treatment. If you do not, please ask the doctor who suggested radio-iodine treatment to explain.

Are There Any Precautions I Should Take?
Because the iodine is radioactive, you will be radioactive for a while after the treatment. This treatment is for your benefit, but after  your treatment anyone who  comes into close contact with you will be exposed to  a small radiation dose, which they do not need. If you take a few simple precautions, you can reduce the dose of radiation  to other people. The advice given is to help protect other people, especially your own family.

Do I Need To Do Anything Before The Treatment?
Yes- if you look after children at home or at work you may need to make alternative arrangements for childcare for several days (up to 27 days) following your treatment. The exact length of time depends on what dose you are given and the age of the children. If you have children at home or work please telephone the department for advice.
Yes – if you suffer from incontinence please telephone the department BEFORE your treatment date
Yes – if you have any concerns about having radio- iodine treatment, or feel the precautions are unacceptable please telephone the department so that you can discuss your concerns. The dose of radio-iodine is ordered in advance especially for you so please contact the department at least a week in advance of your appointment if there is anything you which to discuss.

Should I Tell Anyone If I Am Pregnant or Breast Feeding?

YES PLEASE – This is very important

If you are a woman you will be asked are you or may you be pregnant and you may be asked to have a pregnancy test. If there is any possibility you may be pregnant the treatment must be delayed. If you are breast feeding, you must stop completely before having the radio-iodine treatment. You will not be able to restart. These precautions  are to protect your baby.

You must not become pregnant for at least 4 months after you have had the treatment.

Precautions for Men?

Yes. Men should not father a child for 4 months after the radio-iodine treatment.

What About My Tablets?

Please follow the instructions in the appointment letter. If you are in any doubt please phone for advice.
Anti-thyroid drugs (carbimazole, neomercazole or propylthiouracil) or thyroid hormone tablets (thyroxine) interfere with the radio-iodine treatment. You will usually be asked to stop taking these before coming for treatment.
Please take with you any other tablets and medicines you are taking, including any you may have bought from the chemist or health food shops, as some may prevent your treatment working properly.  You may well be able to continue to take these, but we would like to check.
 
Is The Radio-Iodine Dangerous?
No- over the years this treatment has been given to thousands of patients. We know it is both safe and effective.
The rest of your body, apart from your thyroid will receive a small radiation dose, similar to having an X-ray. Your family and friends may be exposed to a small dose if they come into close contact with you. Please read the advice further on as to how to  reduce this.

How Is The Treatment Given?
Having the treatment is very easy. First of all the staff will explain the treatment to you and make sure that you can understand why you are having the treatment. They will also make sure you understand what you can and cannot do afterwards. You will be asked to sign a form to say you are willing to have the treatment.
You will then be given a small capsule to swallow containing the radioactive iodine. This has no taste and will not make you feel any different.

How Long Will The Radio-iodine Stay In My Body?
Within a few hours most of the radio-iodine will have gone into your thyroid gland. The treatment effect will be concentrated there. Smaller amounts will remain in other parts of your body.
The radio-iodine will gradually disappear from your body. Most will come out in your urine with small amounts in your saliva, nasal secretions and faeces. Also, because of the natural radioactive decay process the amount will be reduced each day. The length time will depend on the amount of radio-iodine you were given.

Will My Thyroid Return to Normal?
Not necessarily. WE aim to give just enough radio-iodine to make your thyroid work normally. Unfortunately, the thyroid gland does not always respond in the same way to the same amount of radio-iodine. Sometimes the thyroid remains overactive, and more than one treatment is needed. Sometimes the thyroid becomes underactive following treatment. This can happen in a few weeks or amy take several years. If this happens, it is easily treated by taking a daily thyroid hormone tablet.

Can Anyone Come With Me When I Come For My Appointment ?
Yes of course but only one person please.  This should not be a child as you will need to avoid close contact with children and pregnant women after your treatment.

How May I Travel Home?
This depends on the amount of radio-iodine you have been given and the length of your journey. Generally you may travel home alone, for instance driving or walking. Usually you can go home in a car or taxi if you are the only person in the back seat and there are no children or pregnant women in the car.
If you travel to hospital by public transport, staff will tell you if it is all right to go home the same way. If they would prefer you did not take public transport, they will arrange transport for you, but please can you tell them in advance about your travel plans (please phone the department in advance if you are travelling on public transport).

Are There Any Precautions When I Go Home?
When you go home, you will be given a card with instructions.
Although the dose to other people is small, it is sensible to make sure it is low as possible.
Certain groups of people such as children and pregnant women are more sensitive to radiation. You will be asked to avoid close contact with these people  for some days after your treatment. The length of time will depend on the dose of radio-iodine you are given.
The closer you are and the more you are in contact (such as standing close) to other peolple the more radiation they receive. You can reduce the dose by moving further away and by reducing the time spent close to them.
During the first 48 hours following treatment  your urine will contain significant amounts of radio- iodine.  To reduce the dose to others please follow the advice given.

How Soon Will I Feel Better?
It takes 6-8 weeks for the thyroid hormone levels to fall to normal.

Are There Any Side Effects From The Treatment?
About 7-20 days after the treatment you may experience a slight increase in the symptoms of your overactive thyroid. This is normal and shows your thyroid is responding quickly to treatment. However if the symptoms are severe or causing you concern – please contact the department or the doctor who sent you for treatment.

You may be given tablets to settle the symptoms. If you have eye problems because of your thyroid gland, this may get worse following treatment. If this applies to you, your doctor will discuss this with you.

What Happens After the Radio-Iodine Treatment?
You will need an appointment with the Endocrinology clinic 6-8 weeks after the treatment and will have bloods tests to check how well your thyroid gland is working.

When May I Go Back To Work?
The instruction Card will give you a date when you can go back to work.
This date depends on the dose of radio-iodine you have been given. It is usually 3-11 days after your treatment.
Please let the department know if you;
• Work with young children (such as a teacher or nurse)
• If you think a small amount of radiation may affect your job (for example if you work with sensitive film or in an area where there is radiation sensitive equipment)
• If you handle food
In these cases the time before you can go back to work may be longer. It is likely to be between 9 and 26 days after your treatment.

How Can I Reduce The Radiation Dose To Other People?

 For the first 48hours
You can avoid passing any radio-iodine to other people if you;
Wash your hands carefully after going to the toilet and rinse the basin
Ensure the toilet is properly flushed (flush twice to be sure)
Use disposal handkerchiefs and dispose of them carefully straight away
Do not prepare food for others using your bare hands
Wash al your crockery and cutlery carefully and separately from those used by other people
If there is a spillage of body fluids on your clothes, wash them separately
Make sure no-one else uses your towels and facecloths. Wash them afterwards in the normal way.

Bathroom hygiene is the main way you can avoid passing on radiation to other people.
The treatment will not make you feel sick, but if you are sick (vomit) within 24 hours of swallowing the radio-iodine capsule, please contact the hospital as soon as possible, using the phone number on your instruction card.

You can;
• Continue normal social contact
• Continue to cook for others
• Continue to use the telephone
• Continue to have usual contact with pets

You must Follow the Instructions on the Card

This will give you 3 Dates
Until the first Date (up to 16 days)
• Avoid close contact (no closer than 1 meter, or 3 feet) with other people, especially children (under 16), pregnant women or women who may be pregnant.
• Avoid going anywhere you may be in close contact with other people for greater than 1 hour, like theatres, pubs or cinemas. You need not avoid normal social contact or activities like shopping.
• Do not sleep in the same bed as a child or a pregnant woman.

Until the second date (up to 22 days)
• Avoid close contact with children under 5 and pregnant women

Until the last date (up to 27 days)
• Continue to avoid close contact with children under 3 and pregnant women.

For the whole period
Carry the instruction card with you all the time.
Postpone hairdresser appointments and routine dental appointments. If you need emergency dental work, please show the dentist your card.
If you need to see your doctor or go to Casualty, please show the doctor your card.

If you travel abroad (after the first date) by ferry or air, please contact us to discuss this. Some airports and ferry terminals have sensitive radiation monitoring devices and you will need a letter saying that you have been given radio-iodine medical treatment.

You will have time to discuss the treatment and ask questions when you are seen in the department on the day of your treatment.
However if you have any major concerns about the treatment or feel  you may not wish to have this, please contact the department where you are having treatment  well before your treatment date to discuss your worries.

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