Cystitis is inflammation of the bladder, most often caused by a bacterial infection. Its hallmark symptoms are a burning sensation when you urinate, a persistent urge to go even when your bladder isn’t full, and passing only small amounts of urine each time. About one in three women will experience at least one episode requiring treatment, and the lifetime risk for women exceeds 60%.
The Core Symptoms
Most people with cystitis notice a cluster of urinary symptoms that develop over a day or two. The most common include:
- Burning or pain during urination, often described as a stinging sensation
- Urinary urgency, a strong, sometimes overwhelming need to urinate right away
- Frequent urination, going far more often than usual but passing only small volumes
- Cloudy or strong-smelling urine
- Blood in the urine, which can range from a faint pink tinge to visibly red
- Pelvic pressure or discomfort, typically felt just below the belly button
- Low-grade fever, generally at or below 38°C (100.4°F)
Blood in the urine is more common than many people expect. Microscopic amounts (only visible on a lab test) show up in 7 to 53% of cases, while clearly visible blood occurs in roughly 1 to 15% of cases. Seeing blood can be alarming, but in the context of cystitis it usually resolves once the infection clears.
Why Cystitis Happens
The overwhelming majority of cases are caused by a type of E. coli bacteria that normally lives in the gut. These bacteria have tiny hair-like structures on their surface that latch onto proteins lining the inside of the bladder. Once attached, they resist being flushed out by the normal flow of urine and begin multiplying, triggering the inflammation you feel as pain and urgency.
Women are far more affected than men because the urethra is shorter, giving bacteria a shorter path to the bladder. Sexual activity, certain types of birth control (like spermicides), and hormonal changes after menopause all increase the likelihood. In men, cystitis is less common but can occur alongside prostate issues or catheter use.
Recurrence Is Common
One frustrating reality of cystitis is that it often comes back. About 24% of college-aged women who get a first infection experience another episode within six months. A large study of over 374,000 women found that roughly 14.5% met the threshold for recurrent infections, defined as three or more episodes in a year or two or more within six months. If you’ve had cystitis before, recognizing the early signs quickly can help you seek treatment sooner.
Interstitial Cystitis Feels Different
Not all cystitis is caused by bacteria. Interstitial cystitis (sometimes called bladder pain syndrome) is a chronic condition where the bladder wall stays inflamed without an active infection. It shares some symptoms with bacterial cystitis, like urgency and frequent urination, but has a distinctive pattern: bladder pain that builds as the bladder fills and then temporarily eases after you urinate.
People with interstitial cystitis also commonly experience pain during sex, caused by spasms in the pelvic floor muscles. The urgency can hit before the bladder has had time to fill, making it feel unpredictable. Unlike a standard bladder infection, interstitial cystitis doesn’t respond to antibiotics and tends to persist for months or years, with symptoms that wax and wane.
Symptoms in Older Adults
Cystitis can look very different in older adults, which makes it easy to miss. The typical burning and urgency may be absent entirely. Instead, older people often present with confusion, drowsiness, increased falls, loss of appetite, or new or worsening incontinence, all without a fever. Delirium was reported in about 29% of older adults with urinary tract infections in one review, making it the most common atypical symptom in this age group.
This is especially tricky in people who already have dementia or hearing difficulties, since they may not be able to describe what they’re feeling. A sudden change in mental clarity or behavior in an older person is worth investigating, even if there are no obvious urinary complaints.
When Symptoms Suggest Something More Serious
Simple cystitis stays confined to the bladder. If the infection travels upward to the kidneys (a condition called pyelonephritis), the symptoms shift noticeably. The key differences to watch for:
- Fever above 38°C (100.4°F). Cystitis alone rarely causes more than a mild temperature bump.
- Pain in the side or lower back, particularly tenderness when you press on the area over your kidneys.
- Nausea or vomiting, which are uncommon with a simple bladder infection.
Cystitis symptoms are localized: burning, urgency, frequency, and pressure near the bladder. The moment you develop a high fever, flank pain, or feel systemically unwell, the infection may have spread beyond the bladder and needs prompt attention.
How Cystitis Is Confirmed
Diagnosis is usually straightforward. A urine dipstick test checks for two markers: one detects an enzyme released by your white blood cells (a sign your immune system is fighting an infection), and the other detects nitrites, a chemical produced when certain gut bacteria break down substances in urine. A positive result on both strongly suggests a bacterial infection. In some cases, a urine culture is sent to a lab to identify the exact bacteria involved, which is especially useful for recurrent infections or when initial treatment doesn’t work.