Care at NUH

Services for Overactive Bladder

Intravesical Botulinum Toxin

Intravesical botox is a procedure that involves an injection of Botulinum Type-A toxin into the muscles lining the bladder wall. The toxin, derived from Clostridium botulinum, binds to the nerves endings, inhibiting excessive contraction (squeezing) of the bladder muscle. This intervention addresses bladder muscle overactivity, improving control and thereby increasing the bladder’s storage capacity for urine. 

The procedure involves the insertion of a a telescope (cystoscopy) into the bladder through the urethra, with several injections of Botox (Botulinum Type-A toxin) into the bladder wall. 

What are the alternatives?

  • Conservative treatments
  • Incontinence pads: For less bothersome symptoms, the option of using incontinence pads to manage urine leakage is available.  
  • Conservative measures: Incorporating lifestyle changes such as weight loss, improved fluid intake and reduced caffeine and alcohol consumption.  
  • Bladder training: Learning techniques to resist the urge to pass urine and improve control. 
  • Medicines: If conservative treatments prove ineffective, medications may be considered.
  • Botulinum toxin-A injections are usually explored when other treatments have not yielded satisfactory results. Alternative procedures to Botulinum toxin-A injections include:
  • Sacral nerve stimulation: Involves implanting a device in the lower back that sends electrical signals to the bladder nerves.
  • Posterior tibial nerve stimulation (PTNS): Electrical stimulation of a nerve near the ankle.
  • Enterocystoplasty: A major operation that enlarges the bladder. 

About the procedure

  • Local anaesthetic gel may be applied to the urethra, and in some cases, a general anaesthetic might be needed. 
  • A cystoscope is introduced into the bladder through the urethra, and a number of Botulinum toxin-A injections will be administered on the bladder wall.

Services for Overactive Bladder

  • While injections are usually not painful, some patients may find them uncomfortable. 
  • Patients can usually can return home shortly after the procedure. 
  • The effects of the injections usually work within days, although it may take up to two weeks for them to fully take effect. 

​Botulinum toxin-A injections are effective in over 7 out of 10 patients (70%), meaning that their urgency and incontinence are either significantly better or cured. The effects of the injections last for around four to 12 months and then the symptoms start to return. As such, patients will need further injections when this happens. There is no limit to how many times of injections, and most people find that having repeated injections work well over many years. 

Risks and side effects

  • Symptoms may return after 4-12 months, requiring repeated injections (common). 
  • Mild burning on passing urine for 24 hours after the procedure (common).
  • Urinary bleeding for 1 - 3 days after the procedure (common). 
  • Insufficient improvement in overactive bladder symptoms despite treatment. 
  • Difficulty in passing urine after the procedure, possible requiring intermittent self-catheterisation (more likely with higher doses).
  • Bladder infection requiring antibiotic treatment.
  • Recurrent urinary tract infections (rare).
  • Allergic reaction to Botox marked by difficulty breathing, swallowing and speaking, requiring emergency treatment (very rare).
  • Generalised weakness in the legs and arms due to Botox, usually resolving without admission or treatment (very rare) 
Percutaneous Tibial Nerve Stimulation (PTNS)

Nerve stimulation, also known as neuromodulation, is a treatment option for overactive bladder when medications prove ineffective or when intolerable side effects arise. It is also considered for individuals experiencing  urinary symptoms caused by neurological conditions. 

Nerve stimulation involves the application of electrical pulses to stimulate the sacral nerves responsible for controlling the bladder and the urination cycle. 

PTNS uses a needle at the level of the ankle to stimulate the tibial nerves which, in turn, affects the sacral nerves.  

Tibial nerve stimulation 

During this procedure, a thin needle connected to an electric current is placed near the ankle. The needle penetrates the skin, stimulating the tibial nerve which extends from the inner part of the ankle, along the leg, up to the sacral nerves in the lower back (Fig. 1). 

A treatment course for tibial nerve stimulation generally includes 12 sessions, conducted weekly at the clinic, each lasting 20-30 minutes. As the initial effects may wear off over time, additional  treatment courses may be needed after the initial 12 sessions. 

Services for Overactive Bladder

Risks of PTNS

PTNS is generally well-tolerated with minimal side effects. Mild pain may be experienced when the needle is being placed, but this subsides once the needle is removed. During the procedure, some individuals may feel a slight aching sensation when the current is running through. 

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