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Why Do I Have a Fever with a UTI?

Maybe you went to your physician with a fever and were told you had a UTI. Your first question might be, “What is a UTI?”


A UTI is an abbreviation for a urinary tract infection. Your urinary tract consists of two kidneys, ureters, a bladder, and a urethra. Your kidneys, located in your back, are just below the rib cage. They filter your blood, remove waste products, and form urine. The urine travels through the ureters and empties into your bladder, where it collects until you feel the urge to urinate. You empty your bladder through your urethra. A UTI is an infection in any part of your urinary tract. The most common UTI is a bladder infection, also known as cystitis.


What is a fever? Your core body temperature is usually about 98.6 degrees Fahrenheit (F). If you have a low-grade fever, your temperature is between 99.1 and 100.4 degrees F. A moderate-grade fever measures up to 102.2, and a high-grade fever can reach 105.8 degrees F.


Many people with a UTI also have a fever.

The Link Between a Fever and a UTI

A fever is the way your body fights a bacterial infection. Your fever depends upon the location of the urinary tract infection. If you have a bladder infection, you may not have any fever or just a low-grade fever. A moderate to high-grade fever indicates that you have a kidney infection.


It is vital to monitor children with high fevers due to the risk of seizure activity.

Most Common Symptoms of a UTI and Fever

Your symptoms result from your body's immune response to an infection. The infection causes inflammation of the infected area which triggers your pain. Symptoms of fever are chills, which can cause shaking, and an increased heart rate. There are different symptoms based on the location of your infection.


  • Bladder infection. The symptoms of a bladder infection are an urge to void, a burning sensation, and lower abdominal and back pain. You may have a low-grade fever or none at all.

  • Kidney infection. A kidney infection causes more severe symptoms of pain in your back or side, nausea and vomiting, and a high-grade fever, which causes shaking and chills.

  • Urethritis. An infected urethra causes urgency, pain, and burning during urination. There may also be some discharge. You most likely will not have a fever.

Ways to Prevent a Fever with a UTI

Since the body’s natural response to fighting an infection is fever, you can treat it but not prevent it. However, you can decrease the severity of your fever by doing the following:


  • Seek timely treatment. Don’t delay calling your doctor, seeing a pharmacist, or attending a health clinic. UTIs don’t get better without intervention. If you have a high-grade fever, feel unwell, and must wait hours to see your physician, consider going to an emergency room. Treatment for a kidney infection is an urgent matter.

  • Rest and practice symptom management. UTIs are very uncomfortable. Take over-the-counter medications to achieve symptom relief. Getting rest will help your body to heal.

  • Drink adequate fluids. It's essential to keep well hydrated. Drinking fluids will help flush your urinary tract system while waiting for the medications to take effect. Drinking cranberry juice helps to reduce symptoms and flush your urinary tract.

  • Prevention. You may not be able to prevent a fever, but you can avoid a UTI. The female anatomy lends to UTIs due to the proximity of the urethra to the anus. Wipe yourself from front to back after urinating or defecating. Urinate after having sex to flush any bacteria out of the urethra. Change into dry clothes after swimming. Avoid baths and bubble baths due to bacteria growth in warm water and irritation from the soap.

If you are a male diagnosed with a UTI, you should ask for an assessment for an enlarged prostate since it may be blocking your urine flow.

The Recovery Period from a Fever with a UTI

Your fever should disappear within 48 hours after beginning your prescribed antibiotics. If it worsens, you should return to the physician, as you may need a different or more potent antibiotic. In severe kidney infections, your physician may prescribe intravenous medication and admit you to the hospital for observation.

Medications That Can Help Treat a Fever with a UTI

The most effective way to treat a fever with a UTI is to take your prescribed antibiotic. The antibiotic will fight the infection which is causing the fever. Always take the full course of your antibiotics. Your physician may ask you for a urine sample to determine the best antibiotic for your infection. If your symptoms persist after completion, call your physician or clinic.


You can also take over-the-counter medications that your physician has approved. Acetaminophen, also known by the trade name Tylenol, can reduce your fever. Another class of drugs that help reduce fever and inflammation is non-steroidal anti-inflammatory drugs (NSAIDs). They go by many trade names, the most common being Ibuprofen. NSAIDs help bring down the fever and reduce pain.


It's essential to read the drug labels and only take the recommended amount. Also, many come under different trade names, which makes it easy to overdose without knowing you are doing so.


Having a UTI with a fever is very uncomfortable. However, taking your prescribed antibiotic will fight the infection, while physically approved over-the-counter medications can reduce fever and keep you comfortable until your body heals.

Resources

Balli, S., Shumway, K. R., & Sharan, S. (2022, September 11). Physiology, Fever. StatPearls [Internet].

https://www.ncbi.nlm.nih.gov/books/NBK562334/


Centers for Disease Control and Prevention. (2021, October 6). Urinary Tract Infection.

https://www.cdc.gov/antibiotic-use/uti.html


Flores-Mireles, A. L., Walker, J. N., Caparon, M., & Hultgren, S. J. (2015, January 1). Urinary tract infections: epidemiology, mechanisms of infection and treatment options. Nature Reviews Microbiology, 13(5), 269–284.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4457377/


Imam, T. H. (2022). Overview of Urinary Tract Infections. Merck Manual.

https://www.merckmanuals.com/en-ca/home/kidney-and-urinary-tract-disorders/urinary-tract-infections-utis/overview-of-urinary-tract-infections-utis

Alice Blackmore

Bio:

Alice Blackmore, MN, RN

Alice Blackmore is a freelance writer, registered nurse, and owner of Insightfulnursing.com.  She has expertise in pediatrics, maternal health, critical care, and long-term care. She now shares her years of experience through writing.