Overactive bladder and urge incontinence

Overactive bladder (or OAB) is a condition that affects 1 in 6 men and women in the UK. People with OAB have difficulty holding on when their bladders are full and often have to rush to the toilet ("urgency"). Most people pass urine 4 or 5 times a day and can comfortably hold around 300-400ml of urine before they need to go. People with an overactive bladder need to go more often than normal (eg 8 or more times) and may only be able to hold a smaller volume in their bladder. About one third find they leak urine before they can reach the toilet (this is called urge incontinence) and some patient have to get up at night to pass urine (nocturia).

The main symptoms of overactive bladder are:

  • urgency (sometimes with incontinence)
  • frequency
  • nocturia (getting up at night to pass urine)


The doctor will also take a detailed account of your bladder problems, do a careful examination, and perform a urine test and a scan of the bladder in the outpatient clinic. 90% of the time, this is all that is required to diagnose the problem and suggest appropriate treatment. Sometimes, further tests may be needed (eg cystoscopy or urodynamics).


There are a variety of treatments which are known to help overactive bladder (OAB) symptoms. Common treatment options include:

  • Conservative treatment
  • Vaginal oestrogen therapy
  • Medications
  • Botox bladder injections
  • Posterior Tibial Nerve Stimulation (PTNS)
  • Sacral Neuromodulation 
  • Surgery

Conservative treatment

Usually, the doctor will try to treat your symptoms without resorting to “invasive” treatments or operations. Many patients will respond well to these “conservative measures”.

  • Caffeine reduction. As well as causing the kidneys to produce more urine, caffeine can also irritate the bladder and make urgency symptoms worse.
  • Alcohol. For some people, alcohol makes their symptoms worse.
  • Bladder training

The aim is to slowly stretch the bladder so that it can hold larger and larger volumes of urine. In time, the bladder muscle should become less overactive and you should become more in control of your bladder.

Pelvic floor exercises

Pelvic floor exercises help to strengthen the muscles that lie at the bottom of the pelvis. These muscles are responsible for supporting the internal organs, including the womb, bladder and rectum. By training these muscles, urgency and incontinence can be improved significantly. Follow this link for further details about Pelvic Floor Exercises.

Oestrogen and medical therapy

Many women develop overactive bladders after going through the menopause. The bladder is very sensitive to hormone levels, and this may affect you even if you are using HRT treatments. Using an oestrogen cream or pessary, which is inserted into the vagina, can help replenish the oestrogen levels and improve OAB symptoms. This type of oestrogen treatment is very safe as only minimal amounts are absorbed into the rest of the body, and it does not have the risks associated with many other types of oestrogen treatments.


Antimuscarinics work by relaxing the bladder muscle and making it less sensitive, which can increase the bladder capacity. These can work well, but side-effects are not uncommon, including dry mouth, dry eyes and constipation.  Mirabegron is a different medication for overactive bladder and works in a different way to the anti-muscarinic tablets described above. The evidence from clinical trials suggests that Mirabegron may be effective even when patients have not responded well to anti-muscarinic tablets. It has few side effects and is a good choice if anti-muscarinics are not well tolerated e.g. due to dry mouth or constipation.

Dementia and medications for OAB

We have long known that some elderly people can become confused while taking some medications. Anti-muscarinics can cause this problem in some people. There has also been some recent evidence that suggests that these tablets might be associated with an increased risk of dementia when used for a long time. Experts currently do not know for certain if anti-muscarinics actually cause dementia and this seems to be a problem mostly for patients who are on lots of medications. These is no concern at all with Mirabegron, as this does not cause confusion and does not increase the risk of dementia.

Botox Bladder Injections

Botox works on the nerve endings of muscles, blocking the release of the chemical that causes the muscle to contract. In patients with an overactive bladder, the bladder muscle often squeezes at the wrong time, causing a desperate urge to pass urine and even incontinence. Botox injections work by reducing these bladder contractions, allowing patients to control their bladders better.

After Botox injections, around 85% of patients have improved incontinence and reduced urgency. The effects last for around 9 months, but the treatment can be repeated whenever needed.

Botox bladder injections can be performed while awake, but some people prefer to have a general anaesthetic. Most patients can home on the same day. A gel containing local anaesthetic is applied to the water pipe to make it more comfortable. A narrow telescope is then passed into the bladder though the urethra and a very fine needle is used to do the injections. The injections can sometimes be uncomfortable, but not usually painful. There are ten injections in total and the procedure takes about 5-10 minutes to do.


Posterior tibial nerve stimulation (PTNS) is a form of neuromodulation used to treat overactive bladder (OAB) and urge incontinence.

When you have the PTNS treatment, a very fine needle (just like an acupuncture needle) is inserted into the lower leg, slightly above the ankle. This is then connected to a device that delivers an electrical pulse to the Tibial nerve, which runs nearby. The treatment continues for 30 minutes but it is not painful.

The treatment is repeated once-a-week for 12 weeks, 30 minutes per session. Patients who respond to treatment may require occasional treatments (about once every 3-4 weeks) to sustain improvements.

Sacral Neuromodulation (SNM)

Sacral nerve stimulation (also called InterStim Therapy or sacral neuromodulation) is a treatment which helps to restore normal bladder function by sending electrical signals to the nerves that control the bladder. It can be used to treat:

  • female urinary retention (inability to pass urine)
  • over active bladder in men and women (including urgency and frequency or urge incontinence)

The Interstim device consists of an electrode (thin wire) which is inserted through the back and a stimulator which is implanted under the skin in the buttock. The stimulator continues to deliver mild electrical pulses to the nerves that control the bladder and help to restore normal function.

There are two types of stimulator available. One has a battery that lasts about 5 years and then needs a minor procedure to change the battery when it is running down. The other has a rechargeable battery. The patient wears a belt round the waist to recharge the battery for about 40 minutes once a week, but the battery will not need any routine changes. Both work equally well, the the rechargeable device is very much smaller. Studies have shown that most patients (about 75%) with urge incontinence who have Interstim treatment show a good improvement in their symptoms, and around half are completely back to normal (that is, they have no more incontinence).

There are relatively few consultants around the UK who offer SNM treatments and it is usually performed in a small number of specialist centres. Richard Parkinson has been the lead urologist for bladder dysfunction and incontinence in Nottingham since 2009 and has developed the SNM service for urinary incontinence in Nottingham.

For further details, please follow this link to the BAUS patient information leaflet on Sacral Neuromodulation.