Bladder Infection

Reviewed/Revised Jun 2023
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What is a bladder infection?

Your bladder is the hollow organ that holds urine until you're ready to urinate (pee). A bladder infection is usually caused by bacteria. Bladder infections are also called cystitis.

  • Bladder infections are common in women and rare in men

  • Bladder infections make you want to urinate more often than normal and sometimes cause pain or burning when you urinate

  • Doctors can usually tell if you have a bladder infection by testing your urine

  • Doctors treat bladder infections with antibiotics

The Urinary Tract

What causes bladder infections?

Bladder infections are caused by bacteria getting into your bladder. Usually, bacteria get in through your urethra. The urethra is the tube that carries urine from the bladder out of the body.

Women are more likely than men to get bladder infections. A woman's urethra is shorter and closer to the vagina and anus, which makes it easier for bacteria to get to the bladder.

For women, the following also raise the chance of getting a bladder infection:

  • Having had other bladder infections, especially if they began when you were young

  • Pregnancy

  • Menopause, because of changes in hormone levels and thinning tissues around the urethra

  • Having sex

  • Using a diaphragm (a rubber birth control device that goes in the vagina)

  • Using a spermicide (a gel that you put in the vagina to kill sperm)

For both women and men, the chance of having a bladder infection is higher if you have:

  • Diabetes

  • A weakened immune system

  • A blockage of urine, such as a bladder stone or narrowing of the urethra

  • A urinary catheter (a thin, flexible plastic tube that is put into your urethra to drain your urine)

  • A procedure where the doctor puts surgical instruments in your urethra

What are the symptoms of bladder infections?

  • The need to urinate more often, including at night

  • A burning or painful feeling when you urinate

  • Pain in your lower belly and sometimes lower back

  • Cloudy urine and maybe some blood in your urine

  • Sometimes fever

Sometimes you may have a bladder infection but no symptoms. This is more common for older people, people with nerve problems in their bladder, and people who have a catheter in their bladder. Sometimes, in older people confusion is the only symptom of a bladder infection.

How can doctors tell if I have a bladder infection?

Your doctor can tell if you have a bladder infection based on:

  • Your symptoms

  • Testing your urine

To test your urine, doctors need a sample that doesn't have any bacteria from your skin in it. So before you urinate, you'll have to clean off the area where your urine comes out. You'll first urinate a little bit in the toilet. You'll then put the urine container in your urine stream and collect a sample. If the doctors don't think this method will give a clean enough sample, they may put a catheter in your bladder to get the sample.

How do doctors treat bladder infections?

Your doctor will give you:

  • Antibiotics

If your urine flow is partly blocked, you may need surgery. If you have diabetes or a weakened immune system, treating those conditions makes it easier to treat the bladder infection.

If you feel a lot of burning when you urinate, doctors may give you a pill that helps relieve the burning until the antibiotics work.

How can I prevent bladder infections?

Women who tend to get bladder infections can:

  • Drink lots of fluids

  • Urinate often

  • Urinate after sex

  • Wipe front to back after pooping

  • Avoid spermicides and diaphragms

People who get a lot of bladder infections may take antibiotics every day to try to prevent such infections. For women who had menopause, doctors may prescribe a cream containing the female hormone estrogen.

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