Intravesical BCG Therapy

Intravesical BCG places a medicine into the bladder to stimulate a local immune response against selected bladder cancers.

It is delivered through a thin catheter rather than through a vein. The treatment acts mainly inside the bladder and is used after a urology assessment, often following removal of visible tumour.

You may be asked to limit fluids before the appointment so the medicine can remain in the bladder for the instructed period. A clinician inserts a catheter, places the BCG solution into the bladder and removes the catheter. You then follow the clinic's instructions for movement, toilet use and cleaning at home.

Bladder irritation is common and may cause burning when passing urine, urgency, frequency, pelvic discomfort, tiredness or a low fever. These effects should be discussed if they are severe or do not settle.

Seek urgent advice for high fever, shaking chills, feeling very unwell, confusion, breathing difficulty, inability to pass urine or persistent heavy blood in the urine. Do not attend treatment while you have a urinary infection or visible blood unless the urology team has advised you.

BCG can reduce the chance that selected non-muscle-invasive bladder cancers recur or progress, but it is not suitable for every tumour and does not remove the need for surveillance. Cystoscopy and other tests help the urologist judge whether treatment is controlling the disease.

BCG is not the same as a routine antibiotic and is not given through an intravenous drip. Follow hygiene instructions carefully because the solution contains live bacteria used for treatment.

It is considered for some people with bladder cancer whose risk of recurrence or progression makes local immune treatment useful. The urologist reviews tumour features, previous procedures, urine symptoms, immune health and whether the bladder can safely receive BCG.

The team checks your symptoms and urine, confirms that BCG is appropriate, and asks about medicines or immune problems. After the catheter delivers the solution, you follow the advised holding and hygiene instructions. Contact details are provided before you leave.

Urinary urgency and flu-like feelings may occur for a short time. Drink according to the advice from your team, rest if needed and follow toilet-cleaning instructions. The next appointment may be adjusted if symptoms have not settled.

Risks include bladder inflammation, urinary infection and, rarely, a serious BCG infection affecting the body. Tell the urology team about fever, worsening pain or urinary difficulty rather than waiting for a routine review.

Depending on tumour findings and response, alternatives may include repeated endoscopic treatment, medicine placed in the bladder, systemic treatment or [Bladder Removal Surgery](/treatments/surgical-oncology/cystectomy/). Your urologist explains the trade-offs.

Seek a urology service experienced in intravesical treatment and bladder surveillance. Ask how to report fever, when to delay a dose, and which hygiene steps apply in your home.