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Internal radiotherapy safety

You need to follow some safety procedures when you have internal radiotherapy. This can include not being in contact with pregnant women and children under 16 for a few days.

The safety procedures you need to take depend on the type of internal radiotherapy you're having. 

Why are safety procedures needed?

With some types of internal radiotherapy you'll be slightly radioactive afterwards.

Treatments involving a permanent implant can make you radioactive for a few months afterwards. Whereas, treatment with an implant that is kept in for a few days will only make you radioactive for a few days. 

Radioactive drinks or liquids can make you radioactive for a few days after treatment. If you have a radioactive liquid, such as iodine, your urine, sweat or poo (faeces) give out a low amount of radiation for a few days.

Even if you are radioactive for a few months after treatment, the amount is usually very low. But hospitals follow particular safety guidelines to keep everyone around you safe. 

Each hospital has slightly different routines but the same safety rules apply across the UK.

How the internal radiotherapy affects you

With brachytherapy, your doctor puts the radioactive implant as close to the cancer as possible. So that the cancer gets a high dose but nearby tissues and further away from the implant the levels of radiation are low. 

For nuclear medicine, the liquid is absorbed by the cancer and the radiation only travels a few millimetres. This means the rest of the body gets a much lower dose and it is normally not enough to harm you. The radiation levels gradually fall as time passes.

After internal radiotherapy treatment

You'll always be told if you will be radioactive after treatment. Your doctor or nurse will tell you about any safety measures you need to follow, including avoiding pregnant women or children under 16. 

If you had a temporary radioactive implant, all the radiation disappears as soon as the implant is removed. You are then not a risk to anyone around you. 

Some implants stay in for a few days. You usually have to stay in hospital in a separate room whilst you have them in. 

You might give off a low level of radioactivity for a few days after having radioactive seeds put in. Your doctor or nurse will tell you about this. They advise you on how to restrict your activity, until the radiation can't be detected outside the body. 

You might need to:

- stay in hospital for a few days
- avoid close contact with pregnant women or children
- avoid public transport

It usually takes a few days for the radioactivity to reduce if you have had a liquid radiotherapy treatment.

Whether or not you go home on the same day will depend on the dose of radiation you have. The hospital staff make sure that the radioactivity is at a safe level for your friends and family before you go home. After you leave hospital the staff might give you some safety steps to follow for a while, for instance if you are in contact with children or pregnant women.

The safety measures are there to protect you, your family and the hospital staff.

Safety procedures

Please note that all these safety guidelines are not relevant to every internal radiotherapy treatment. It is helpful to run through this list with your doctor or specialist nurse to see which applies to you.

While having treatment

  • You might be in a special side room, away from the main ward for 1 or 2 days.
  • The doctors and nurses looking after you only stay in your room for short periods at a time.
  • Staff wear badges that monitor their exposure to radiation and make sure they keep to a safe level.
  • Staff and visitors need to stay a little way away from your bed – the further away they are, the less exposure they have to the radiation.
  • The nurses might use an instrument called a scintillation counter to monitor radiation levels in anything taken out of the room, such as bed linen.
  • You can only have a limited number of visitors.
  • Visitors are asked to stay a short time and may need to sit some distance away from you or talk to you from the doorway.
  • Children under 16 and pregnant women are not allowed to visit.
  • You can take books, magazines, and some electronic devices into the room.
  • If you had a radioactive drink, your urine might be slightly radioactive for a few days – you may need to use the toilet sitting down and wear gloves when you wipe yourself.

After your treatment

  • You might be given a card to keep with you for a certain period of time in case of a medical emergency.
  • If a medical emergency happens, let your doctor know that you have had internal radiotherapy treatment.
  • For a few days after a radioactive drink you might need to flush the toilet twice, each time you use it.
  • If you had internal radiotherapy seeds for prostate cancer and one comes out when you empty your bladder, don't touch it. Use tongs to pick it up and flush it down the toilet. Tell your doctor.
  • You might need to wear a condom during sex for a few months after internal radiotherapy for prostate cancer. This is in case a seed comes out during sex but this very rarely happens.

Your feelings about the precautions

The radiotherapy safety measures can add to the worries you might already have about your treatment. But it's important to remember that in everyday life we are all exposed to a small amount of radiation, and this doesn't harm us. 

There are also safety limits for radiation and national guidelines that anyone using radiation has to follow.

People are different in the way they handle their worries. Some find it easier to know everything about their treatment, while others like to know as little as possible.

You can speak to your doctor, nurse or radiographer if you need them to explain anything. It often helps to bring your fears and worries into the open by talking to the staff, or to your family and friends.

Coping with isolation

Staying in hospital in a single room can be lonely. It can help to talk to your nurses about your worries. They can reassure you.


Taking in some of your personal things can make the room on the ward feel more homely. Books, photographs and ornaments can brighten it up.

You can also take in a mobile phone, laptop, electronic tablet or music player to make the time pass more enjoyably.

Nuclear medicine

You might not be able to take personal items to the room on the ward. This is because the items could become contaminated with radioactivity from your sweat.

Wards, nuclear medicine departments and radiotherapy departments have limited storage space for contaminated articles.

Sometimes a moist wipe can be used to clean your personal items so that they aren't radioactive. The staff let you know what you can and can't bring in beforehand.

Information and help

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