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Patients & Visitors



Treatment: BCG

How does it work?

BCG is a vaccine which is used to prevent tuberculosis (TB). But it’s also a helpful treatment for some early bladder cancers.  Like chemotherapy it is inserted into the bladder via a catheter.

BCG is a type of immunotherapy which stimulates the body’s immune system to destroy cancer cells. BCG makes the bladder react in a way that triggers the body’s immune system to get rid of cancer cells in the bladder.

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When BCG is used

BCG is usually given to people with early bladder cancer who have a high risk of the cancer coming back and growing into the muscle (becoming invasive).

BCG helps prevent the cancer from coming back in the bladder and also reduces the chances of it becoming invasive. Your specialist will explain why BCG is the most appropriate treatment for you.

You’ll usually have your treatment once a week for six weeks. If the BCG treatment is working well for you it can then be given every six months, once a week for three weeks. This is called maintenance therapy. Maintenance therapy can continue for up to three years. Your specialist will talk to you about how long your treatment will go on for.

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How it's given

BCG treatment is given in the urology outpatient department by one of our nurse specialists. It takes up to three hours and you can usually go home as soon as it’s finished. It might be a good idea to ask someone to collect you, particularly the first time.

Unlike chemotherapy into the bladder, BCG treatment is never given immediately after surgery to remove bladder tumours. There needs to be a delay, usually of at least two weeks after surgery, before you can have it. You won’t be given treatment with BCG if you’re unwell or have a urine infection.

You’re usually asked to limit the amount of liquid you drink before your treatment. This will help increase the concentration of BCG in your bladder. Also, drinking too much before your treatment may make your bladder feel uncomfortably full. If you normally take water tablets (diuretics), take them later in the day after your treatment. Your nurse or doctor will give you more advice about preparing for your treatment.

You’ll have a catheter put into your bladder. Your nurse will then put the liquid vaccine directly into your bladder through the catheter.  The catheter is left in and clamped to keep the BCG in your bladder for the next two hours. You can walk around during this time.

The BCG will be drained through the catheter which is then removed.

After your treatment you’ll need to take some precautions. This is because BCG is a live vaccine and other people shouldn’t be exposed to it.

For the next six hours, you’ll need to avoid your urine splashing on the toilet seat and getting any urine on your hands. It might be easier for men to sit down when they’re using an ordinary toilet, although using a stand up urinal should be okay. The main thing is to avoid splashing urine and spreading the vaccine. You’ll also be asked to put undiluted bleach into the toilet bowl to destroy any live vaccine and leave it for 15 minutes until you flush. Your nurse will give you more advice about this.

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Side effects

Because BCG goes directly into the bladder, most of the side effects are linked with the bladder. They usually go away 1-2 days after your treatment. The most common ones are:

  1. needing to pass urine more often
  2. pain when you pass urine
  3. blood in the urine
  4. flu-like symptoms such as tiredness, general aching and a temperature.

If they don’t get better, contact your doctor. Drinking lots of fluids can help flush the drug out of your bladder and reduce some of these effects. Taking simple painkillers can also help.

Rare side effects can include a continuing high temperature (fever), pain in your joints and a cough. If you have any of these symptoms, or if you feel generally unwell, contact your doctor immediately. These symptoms could be a sign of a more serious infection due to BCG that needs to be treated urgently. If this happens, you’ll be treated with the same drugs (antibiotics) that are used to treat TB.

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