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What causes OAB?
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Overactive bladder (OAB) is NOT just a natural part of aging.
It's a real medical condition.

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To find out more about myths in OAB see our OAB Myths and Facts page.OAB often starts when people hit their 30s or 40s. But it is not normal at any age. It affects about 50 million people worldwide.
How a healthy bladder works
Each time you eat and drink, your body absorbs liquids. The kidneys filter out waste and make urine. The urine is stored in your bladder.
Nerves tell the brain when the bladder is full. That's when you get the feeling that you need to go to the bathroom.
Normal bladder control
When you decide it’s time to go to the toilet, your brain tells the bladder muscle to contract, or squeeze.
At the same time, pelvic floor muscles around the urethra are told to relax. That lets the urine out when and where you want.

Overactive bladder
With overactive bladder (OAB), the bladder muscle squeezes too often or when you don’t want it to. This can cause sudden, frequent, strong urges to go to the toilet.
And, it may cause you to worry about wetting or leaking accidents.
There are treatments that can help calm the overactive muscle that causes those frequent, strong urges. And, it can help you to be more at ease about your bladder control.
The causes of OAB
Overactive bladder (OAB) occurs when the bladder muscle is too active. This means that the muscle contracts, or squeezes, too often or when you don’t want it to. This can cause a strong, sudden urge to urinate even when the bladder is not full. In many cases, an exact cause cannot be found. However, often OAB is caused by:
An enlarged prostate may be cause of OAB. But men can have OAB even without having an enlarged prostate. In fact, just about the same number of men suffer from OAB as women. If you are a man with OAB symptoms, talk to your doctor.
Sometimes damage to the nerves of the bladder, to the nervous system (spinal cord and brain), or to the muscles themselves can cause the bladder muscle to contract, or squeeze, when you don’t want it to. For example, multiple sclerosis, Parkinson's disease, Alzheimer's disease, stroke, and injury can harm bladder nerves or muscles.
Childbirth, for women can also cause nerve damage that affects bladder control.
Some medicines, such as pills to treat swelling or high blood pressure
Methods to treat OAB



