What is Overactive Bladder?

Overactive bladder (OAB) is a common condition where the bladder muscle, known as the detrusor, contracts more frequently than it should or does so involuntarily. If you have OAB, you might find yourself needing to urinate more often than feels normal, or experiencing sudden urges that are difficult to control. Some people with OAB also experience urge incontinence — leaking urine before reaching the toilet.

It’s worth noting that OAB is a syndrome defined by symptoms rather than a specific disease. The International Continence Society defines it as “urgency, with or without urge incontinence, usually with frequency and nocturia” in the absence of infection or other obvious causes 1.

Most people with OAB have no identifiable neurological problem — their nervous system is functioning normally. This is sometimes called “idiopathic” OAB, meaning we don’t fully understand why the bladder behaves this way.

What Causes Overactive Bladder?

Pinpointing a single cause for OAB can be frustrating because often there isn’t one clear culprit. That said, several factors are known to contribute to or trigger overactive bladder symptoms:

Urinary tract infections: A bacterial infection in the bladder can irritate the bladder lining and cause urgency and frequency. If your symptoms appeared suddenly, a urinary tract infection should be ruled out first. The good news is that if infection is the cause, treating it often resolves the OAB symptoms.

Bladder outlet obstruction: In men, an enlarged prostate (benign prostatic hyperplasia) can partially block urine flow. The bladder works harder to push urine past the obstruction, and over time this can lead to overactive bladder symptoms. Women can also experience obstruction from conditions like pelvic organ prolapse or previous surgery.

Neurological conditions: The brain normally sends signals telling the bladder when to hold and when to empty. Conditions that disrupt these signals — Parkinson’s disease, multiple sclerosis, stroke, or spinal cord injuries — can result in the bladder contracting when it shouldn’t. This is sometimes called neurogenic bladder, though the symptoms often overlap with OAB.

Medications: Some drugs can worsen OAB symptoms. Diuretics (water tablets) increase urine production, which means more trips to the toilet. Other medications like phenothiazines and opioids can affect bladder function in different ways. If your symptoms started or worsened after beginning a new medication, it’s worth discussing this with your doctor.

Diet and drinks: Caffeine and alcohol are well-established bladder irritants. They’re both diuretics, meaning they increase urine production, and caffeine in particular can stimulate the bladder muscle directly 2. Cutting back on tea, coffee, cola, and alcohol often helps reduce symptoms, though admittedly this isn’t the advice most people want to hear.

Age-related changes: The bladder muscle can become less flexible with age, reducing its capacity to store urine. The prostate tends to enlarge in older men. These changes don’t make OAB inevitable, but they do make it more common in older adults.

Excess weight: Carrying extra weight puts pressure on the bladder and pelvic floor muscles. Studies have shown that weight loss can improve OAB symptoms, though it’s rarely a complete solution on its own 3.

Symptoms of Overactive Bladder

The hallmark symptoms of OAB include:

Urgency: This is the defining symptom — a sudden, compelling need to urinate that’s difficult to defer. It’s not just “I need to go soon” but “I need to go right now.” This urgency can strike without warning and may wake you from sleep.

Frequency: Needing to urinate more than eight times during waking hours is generally considered frequent. Some people with OAB go 10, 15, or even 20 times per day. The bladder may not even be full — it just feels like it is.

Nocturia: Getting up more than once per night to urinate disrupts sleep and can lead to daytime fatigue. Nocturia has multiple potential causes, but OAB is one of the most common.

Urge incontinence: Not everyone with OAB experiences incontinence, but about one-third do 4. This means leaking urine before reaching the toilet. The leaks can range from a few drops to complete bladder emptying.

Nocturnal enuresis: Wetting the bed during sleep. This is less common in adults with OAB but does occur.

You don’t need all these symptoms to have OAB. Urgency alone, if it’s troublesome, may warrant investigation and treatment.

How Common is Overactive Bladder?

OAB affects a substantial number of adults. Large population studies suggest that roughly one in six adults — around 16-17% — experience some OAB symptoms 5. Women and men are affected at similar rates, though the symptom profiles differ somewhat (men are more likely to have frequency without incontinence; women are more likely to experience urge incontinence).

The condition becomes more prevalent with age. Among people over 65, estimates suggest that 30% or more may experience OAB symptoms. However, OAB isn’t confined to older adults — it can affect people at any age, including younger women and men.

Here’s the thing many people don’t realise: the majority of those with OAB symptoms never seek medical help. Some feel embarrassed. Others assume it’s an inevitable part of ageing or, for women, a consequence of childbirth that can’t be fixed. Neither assumption is accurate. OAB is a medical condition with effective treatments, and it’s certainly worth discussing with a healthcare provider.

How Overactive Bladder Affects Daily Life

Living with OAB can be genuinely difficult. The symptoms intrude on practically every aspect of life:

Travel and outings: Planning any trip — whether it’s a bus journey, a flight, or a walk in the park — often revolves around toilet locations. Some people with OAB become skilled at mentally mapping every available bathroom in their vicinity. This constant vigilance is exhausting.

Work: Frequent toilet breaks can be embarrassing and may affect productivity. Some people feel they can’t take certain jobs or attend long meetings because of their bladder.

Sleep: Getting up multiple times per night to urinate fragments sleep. The resulting fatigue affects mood, concentration, and overall wellbeing. Partners’ sleep is often disrupted too.

Social life and relationships: Fear of accidents or the need to be near a toilet can lead to social withdrawal. Intimate relationships may suffer, particularly if coital incontinence (leaking during sex) occurs.

Emotional wellbeing: Many people with OAB report feelings of embarrassment, frustration, and loss of control. Depression and anxiety are more common in people with OAB than in the general population.

Practical burdens: If incontinence occurs, there’s extra laundry, the cost of pads or protective underwear, and concerns about odour.

It’s not a trivial condition to live with. If OAB is affecting your quality of life, that’s reason enough to seek help.

Diagnosing Overactive Bladder

If you’re experiencing OAB symptoms, your doctor will likely:

Take a detailed history: When did symptoms start? How often do you urinate? Do you leak urine? Are there particular triggers? What medications do you take? The answers help distinguish OAB from other conditions.

Perform a physical examination: This may include an abdominal examination and, depending on your symptoms, a pelvic examination in women or a prostate examination in men.

Test your urine: A urine sample rules out infection and checks for blood or other abnormalities.

Ask you to keep a bladder diary: Recording when you drink, when you urinate, and any leakage episodes over a few days gives useful objective information.

In some cases, additional tests may be recommended:

Post-void residual measurement: An ultrasound scan after urinating checks whether your bladder is emptying properly.

Urodynamic studies: These tests measure bladder pressure and function. They’re not always necessary but can help if the diagnosis is uncertain or if initial treatments haven’t worked.

Cystoscopy: A thin camera passed into the bladder. This isn’t routine for OAB but may be used to rule out other conditions if there are concerning features like blood in the urine.

Treatment Options

OAB treatment typically follows a stepped approach, starting with conservative measures and progressing to more intensive interventions if needed.

Lifestyle modifications

These are usually the first step and have no side effects:

Fluid management: Drinking the right amount — neither too much nor too little — helps. Around 1.5 to 2 litres per day is generally recommended, though this varies with activity level and climate. Reducing fluids in the evening can help with nocturia.

Dietary changes: Reducing or eliminating caffeine (coffee, tea, cola, energy drinks, chocolate) and alcohol often improves symptoms. Some people find acidic foods, artificial sweeteners, or spicy foods irritating, though this varies between individuals.

Weight loss: If you’re overweight, losing even a modest amount of weight can reduce OAB symptoms.

Bladder training: This involves gradually increasing the time between toilet visits. If you currently go every hour, you might aim for every hour and fifteen minutes, then gradually extend further. The goal is to retrain the bladder to hold more urine comfortably. It requires patience — improvements typically take weeks to months — but it can be effective 6.

Pelvic floor exercises: Strengthening the pelvic floor muscles (Kegel exercises) can help control urgency and reduce incontinence. A physiotherapist specialising in pelvic health can ensure you’re doing the exercises correctly.

Medications

If lifestyle measures aren’t enough, medications are the next step. The main drug classes used for OAB are:

Antimuscarinics (anticholinergics): These include oxybutynin, tolterodine, solifenacin, darifenacin, fesoterodine, and trospium. They work by blocking signals that cause the bladder muscle to contract. Common side effects include dry mouth, constipation, blurred vision, and cognitive effects (particularly concerning in older adults). Extended-release formulations tend to have fewer side effects.

Beta-3 agonists: Mirabegron and vibegron work by relaxing the bladder muscle through a different mechanism. They may be better tolerated than antimuscarinics for some people, particularly regarding cognitive effects.

Finding the right medication often involves some trial and error. What works well for one person may cause intolerable side effects in another.

Other treatments

For people who don’t respond adequately to lifestyle changes and medications:

Botulinum toxin (Botox) injections: Injected into the bladder wall during a cystoscopy, Botox temporarily paralyses overactive bladder muscles. Effects typically last 6-12 months. The main risk is urinary retention (difficulty emptying the bladder) requiring self-catheterisation.

Nerve stimulation: Sacral neuromodulation involves a small device implanted near the sacral nerves that control the bladder. Posterior tibial nerve stimulation (PTNS) is a less invasive alternative involving regular sessions where a needle electrode near the ankle sends electrical pulses to nerves connected to the bladder.

Surgery: Rarely, if other treatments fail, surgery to increase bladder capacity may be considered. This is a major undertaking with significant risks and is reserved for severe cases.

When to See a Doctor

You should consult a healthcare provider if:

OAB symptoms are affecting your quality of life
You’re getting up frequently at night to urinate
You’re experiencing incontinence
You see blood in your urine (this needs investigation regardless of other symptoms)
You have pain when urinating
Symptoms appeared suddenly or are getting worse

Don’t put off seeking help because of embarrassment. Healthcare professionals deal with bladder problems routinely. Effective treatments exist, and most people can achieve significant improvement in their symptoms.

References

Abrams P, et al. The standardisation of terminology of lower urinary tract function. Neurourol Urodyn. 2002;21(2):167-78.
Gleason JL, et al. Caffeine and urinary incontinence in US women. Int Urogynecol J. 2013;24(2):295-302.
Subak LL, et al. Weight loss to treat urinary incontinence in overweight and obese women. N Engl J Med. 2009;360(5):481-90.
NHS. Urinary incontinence. 2024. Available at: https://www.nhs.uk/conditions/urinary-incontinence/
Irwin DE, et al. Population-based survey of urinary incontinence, overactive bladder, and other lower urinary tract symptoms in five countries. Eur Urol. 2006;50(6):1306-15.
Fantl JA, et al. Efficacy of bladder training in older women with urinary incontinence. JAMA. 1991;265(5):609-13.