What Is a Urinary Tract Infection (UTI)?

A UTI, also known as a bladder infection, is a common condition that occurs when bacteria enters the urinary tract. Most UTIs involve the lower urinary tract, which includes the bladder and urethra. If a UTI isn't treated, it can also spread to the kidneys.
UTIs are easily treated with antibiotics and typically last for several days.
Signs and Symptoms of a Urinary Tract Infection
- Pain in your pelvic area
- Frequent urination
- Persistent urge to urinate
- Pain during urination
- Cloudy, strong-smelling urine
- Blood in your urine
- Urinary incontinence
- Mental confusion
- Fatigue
- Fever
- Chills and shaking
- Pain in the back or side
- Nausea
- Vomiting

Causes and Risk Factors of Urinary Tract Infections
Normally, your urinary system flushes out any lingering bacteria before it causes problems. Sometimes this fails, which can lead to infection. E. coli is the most common cause of urinary tract infections, which is a type of bacteria typically found in your lower intestines.
Anyone can get a urinary tract infection, but they are more common in women. This is because females have a urethra that is shorter and closer to the anus.
- Perimenopause and menopause, which can change the vaginal microbiome
- Birth control such as diaphragms or spermicides
- Low fluid intake
- Constipation
- Incomplete bladder emptying
- A blockage in the urinary tract, such as a kidney stone or enlarged prostate
- A suppressed immune system
- Using a catheter
- Urinary procedures, such as an exam or surgery
How Is Urinary Tract Infection Diagnosed?
- Urinalysis This involves providing a urine sample, which your doctor will send to a lab to test for signs of a UTI, such as bacteria or white or red blood cells.
- Urine Culture A urine sample may also be used to grow and identify any bacteria that might be present.
- Imaging Tests If your infection doesn't respond to treatment, your healthcare team can use imaging tests to examine the structures of your urinary tract. Imaging tests include ultrasound, CT scan, and MRI.
- Cystoscopy For recurrent UTIs, your healthcare provider may recommend a cystoscopy, which involves inserting a long, thin tube with a lens into your urethra to examine your bladder.
Treatment and Medication Options for Urinary Tract Infections
Antibiotics
- Nitrofurantoin (Macrodantin, Macrobid, Furadantin)
- Trimethoprim and sulfamethoxazole (Bactrim, Septra, Sulfatrim)
- Fosfomycin (Monurol)
- Cephalexin (Biocef, Daxbia, Keflex)
- When symptoms occur
- After sex
- Every day or every other day, for six months or more
Home Remedies
- Apply a heating pad to your abdomen to lessen pressure and discomfort.
- Drink plenty of water to dilute your urine and flush out bacteria.
- Avoid beverages that can irritate your bladder, such as alcohol, coffee, and drinks containing citrus.
Lifestyle Changes and Prevention of Urinary Tract Infections
There are several steps you can take to reduce your risk of getting a UTI.
- Drink plenty of water and other liquids to flush out bacteria.
- Urinate as soon as you feel the need, and try to completely empty your bladder.
- If you are a woman, wipe from front to back after urinating or having a bowel movement.
- Urinate before and after sexual activity.
- Avoid tight-fitting clothing and materials that can create a moist environment for bacteria.
- Avoid vaginal deodorants, douches, powders, and other potentially irritating feminine products.
- Use a method of birth control other than a diaphragm, spermicide, or unlubricated condoms.
- Manage constipation.
How Long Does a Urinary Tract Infection Last?
If you have chronic UTIs or your symptoms aren't improving, you may need a stronger course of antibiotics or you may need to take them for longer. If your infection is resistant to antibiotics or you have a kidney infection, you may require intravenous (IV) antibiotics given at a hospital.
Complications of Urinary Tract Infections (UTIs)
Most UTIs don't cause serious issues if they are treated quickly. But delaying treatment can increase your risk of complications.
- Kidney Damage Without treatment, a UTI can spread from your bladder to your kidneys and cause permanent damage.
- Narrowing of the Urethra in Men Recurring infections can cause scarring in the urethra, making it more difficult to urinate.
- Sepsis An untreated UTI can increase your risk of sepsis, a life-threatening overreaction to an infection.
The Takeaway
- A urinary tract infection (UTI) occurs when bacteria, such as E. coli, migrates to your urinary tract and spreads.
- Common symptoms of a UTI include a strong urge to urinate, painful or frequent urination, and strong-smelling or cloudy urine.
- Treatment for a UTI involves antibiotics, and symptoms typically resolve within a few days. Lifestyle changes, like staying hydrated, wiping from front to back, and avoiding tight-fitting clothing can help prevent UTIs.
- If you have UTI symptoms, contact your doctor as soon as possible to discuss treatment options. Without treatment, a UTI can spread to your kidneys and potentially lead to kidney damage.
Resources We Trust
- Cleveland Clinic: Urinary Tract Infections
- Office on Women's Health: Urinary Tract Infections
- American Pregnancy Association: Understanding UTIs in Pregnancy
- MedlinePlus: Urinary tract infection: Children
- National Institute of Diabetes and Digestive and Kidney Diseases: Kidney Infection (Pyelonephritis)
- Urinary Tract Infection (UTI): Symptoms and Causes. Mayo Clinic. September 26, 2025.
- Urinary Tract Infections. Cleveland Clinic. April 6, 2023.
- Urinary Tract Infection Basics. Centers for Disease Control and Prevention. January 22, 2024.
- Urinary tract infection (UTI): Diagnosis and Treatment. Mayo Clinic. September 26, 2025.
- Bono MJ. Uncomplicated Urinary Tract Infections. StatPearls. February 21, 2025.
- Tan-Kim J et al. Efficacy of vaginal estrogen for recurrent urinary tract infection prevention in hypoestrogenic women. American Journal of Obstetrics and Gynecology. May 8, 2023.
- Understanding UTIs in Pregnancy: Causes and Prevention. American Pregnancy Association.

Allison Buttarazzi, MD
Medical Reviewer
Allison Buttarazzi, MD, is board-certified in internal medicine and lifestyle medicine, and is a certified health and well-being coach. In her primary care practice, Dr. Buttarazzi...

Holly Pevzner
Author
Holly Pevzner is a writer who specializes in health, nutrition, parenting, and pregnancy. She is currently a staff writer at Happiest Baby. Her work, including essays, columns, fea...