What is acute cystitis?

Acute cystitis is a sudden inflammation of the urinary bladder. Most of the time, a bacterial infection causes it. This infection is commonly referred to as a urinary tract infection (UTI).

Irritating hygiene products, a complication of certain diseases, or a reaction to certain drugs can also cause acute cystitis.

The treatment for acute cystitis due to a bacterial infection involves antibiotics. The treatment for noninfectious cystitis depends on the underlying cause.

The symptoms of acute cystitis can come on suddenly and can be very uncomfortable. The most common symptoms include:

  • a frequent and strong urge to urinate even after you empty your bladder, which is called frequency and urgency
  • a painful or burning sensation when urinating, which is called dysuria
  • foul- or strong-smelling urine
  • cloudy urine
  • a sensation of pressure, bladder fullness, or cramping in the middle of the lower abdomen or back
  • a low-grade fever
  • chills
  • the presence of blood in the urine

The urinary system consists of the:

  • kidneys
  • ureters
  • urinary bladder
  • urethra

The kidneys filter waste from your blood and create urine. The urine then travels through tubes called ureters, one on the right and one on the left, to the bladder. The bladder stores the urine until you’re ready to urinate. Urine then travels out of the body through a tube called the urethra.

The most frequent cause of acute cystitis is an infection of the bladder caused by the bacterium E. coli.

Bacteria that cause UTIs typically enter the urethra and then travel up to the bladder. Once in the bladder, the bacteria stick to the bladder wall and multiply. This leads to inflammation of the tissue lining the bladder. The infection can also spread to the ureters and kidneys.

Although infections are the most common causes of acute cystitis, several other factors can cause the bladder and lower urinary tract to become inflamed. These include:

  • certain medications, particularly the chemotherapy drugs cyclophosphamide and ifosfamide
  • radiation treatment of the pelvic area
  • the long-term use of a urinary catheter
  • sensitivities to certain products, such as feminine hygiene sprays, spermicidal jellies, or lotions
  • complications of other conditions, including diabetes mellitus, kidney stones, or an enlarged prostate (benign prostatic hypertrophy)

Women are more prone to acute cystitis than men because their urethra is shorter and closer to the anal area, which can harbor harmful bacteria. This makes it easier for bacteria to get to the bladder. More than half of all women experience at least one lower UTI in their lifetime.

The following factors can also increase your risk of acute cystitis:

  • engaging in sexual activity
  • using certain types of birth control such as diaphragms and spermicidal agents
  • wiping your genitals from the back toward the front after using the bathroom
  • experiencing menopause, as less estrogen causes changes in the urinary tract that make you more susceptible to infection
  • being born with abnormalities in the urinary tract
  • having kidney stones
  • having an enlarged prostate
  • using antibiotics frequently or for prolonged periods
  • having a condition that impairs the immune system, such as HIV or immunosuppressant therapy
  • having diabetes mellitus
  • being pregnant
  • using a urinary catheter
  • having urinary surgery

Your doctor will ask about your symptoms and your medical history. Be sure to tell your doctor when your symptoms started and if anything you do makes them worse. Also, inform your doctor of any medications you’re taking or if you’re pregnant.

Your doctor might recommend certain tests, including:


If your doctor suspects an infection, they’ll likely ask for a sample of urine to test for bacterial presence, bacterial waste product, or blood cells. Another test called a urine culture might be done in a laboratory to identify the exact type of bacteria causing the infection.


Your doctor will insert a thin tube with a light and a camera called a cystoscope into your bladder through your urethra to look at the urinary tract for signs of inflammation.


This type of test usually isn’t required, but if your doctor can’t figure out what’s causing your symptoms, imaging might be useful. Imaging tests, such as an X-ray or ultrasound, can help your doctor see if there’s a tumor or other structural abnormality causing the inflammation.

Treatment involves a course of antibiotics for three to seven days if the cystitis is caused by a bacterial infection and it isn’t a recurrent UTI, which may require a longer course.

Your symptoms will likely start to go away in a day or two, but you should continue taking the antibiotics for however long your doctor prescribed. It’s important to make sure the infection is completely gone so that it doesn’t come back.

Your doctor may also prescribe a urinary tract pain reliever such as phenazopyridine for the first couple of days to help reduce your discomfort while the antibiotics take effect.

Treatment for noninfectious types of acute cystitis depends on the exact cause. For example, if you’re allergic or intolerant to certain chemicals or products, the best treatment is to avoid these products altogether.

Pain medications are available to treat cystitis caused by chemotherapy or radiation.

If you’re experiencing the symptoms of acute cystitis, you can help ease your discomfort at home while you wait for antibiotics or other treatments to work. Some tips for coping at home include the following:

  • Drink lots of water.
  • Take a warm bath.
  • Apply a heating pad to the lower abdomen.
  • Avoid coffee, citrus juices, spicy foods, and alcohol.

Many people drink cranberry juice or take cranberry extract supplements to try to prevent UTIs and other forms of acute cystitis, or to ease the symptoms. Some evidence suggests that cranberry juice and cranberry products can fight infections in the bladder or reduce discomfort, but the evidence isn’t conclusive.

One recent study in prostate cancer patients with cystitis caused by radiation treatment found that cranberry supplements significantly reduced urinary pain and burning compared to men who didn’t take the supplement.

You can drink cranberry juice if you think it helps. However, it’s good to be careful about how much you drink since fruit juices are often very high in sugar.

D-mannose is also a potential alternative for preventing or treating acute cystitis. It’s thought that the ability of bacteria to adhere to the urinary bladder wall and cause UTIs may be impeded by D-mannose.

However, the studies that have been done up to now are limited, and further research is needed to see if any strong evidence exists for the effectiveness of this therapy. Taking D-mannose may also result in potential side effects such as loose stools.

Most cases of acute bacterial cystitis are easily treated with an antibiotic. However, you should seek immediate medical attention if you have any of the symptoms of a kidney infection. The symptoms of a kidney infection include:

  • severe pain in the low back or side, which is called flank pain
  • a higher-grade fever
  • chills
  • nausea
  • vomiting

Most cases of acute cystitis go away without complications if they’re adequately treated.

A kidney infection is rare, but it can be dangerous if you don’t get treatment for it right away. People with a weakened immune system or an existing kidney condition are at a higher risk of this type of complication.

You can’t always prevent acute cystitis. Follow these tips to reduce the risk of bacteria entering your urethra and to prevent irritation of your urinary tract:

  • Drink plenty of water to help you urinate more frequently and flush bacteria out of your urinary tract before an infection begins.
  • Urinate as soon as possible after sexual intercourse.
  • Wipe from front to back after a bowel movement to prevent bacteria from spreading to the urethra from the anal region.
  • Avoid using feminine products near the genital area that can irritate the urethra, such as douches, deodorant sprays, and powders.
  • Maintain personal hygiene and wash your genitals every day.
  • Take showers instead of baths.
  • Avoid using birth control methods that can lead to altered bacterial growth, such as diaphragms or spermicide-treated condoms.
  • Don’t delay using the toilet for too long if you have the urge to urinate.

You can also include cranberry juice or cranberry supplements in your diet, but the current evidence for how effective this is for preventing acute infective cystitis is inconclusive. D-mannose may be an option to try to prevent recurrent UTIs, but at this time, the evidence for its effectiveness at doing so is also limited and inconclusive.