Urinary tract infections (UTIs) can sometimes cause fever. This is more likely if the infection is severe or spreads to the kidneys.

Generally, UTIs can affect the bladder, the kidneys, and the tubes connected to them. They can be painful and uncomfortable, but symptoms usually pass within a few days. Doctors usually treat UTIs with a course of antibiotics.

An upper UTI, which primarily affects the kidneys or the ureter — the tubes connecting the kidney to the bladder — can lead to fever.

Anyone with a high fever needs to seek medical attention to prevent further complications.

In this article, we explore the relationship between UTIs and fever, discussing symptoms, causes, treatment options, and when to seek medical attention.

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Yes, a UTI can cause fever. UTIs occur when bacteria enter the urinary tract, including the urethra, kidneys, ureters, and bladder. This can lead to infection and subsequent inflammation.

Common symptoms of UTIs include:

In some cases, people with UTIs may experience symptoms, such as fever, indicating a more severe infection. A severe infection is also known as a complicated UTI or an upper UTI.

Fever is the body’s natural response to infection, signaling that the immune system is actively trying to fight off the invading bacteria.

When a UTI progresses to the point of causing fever, it usually means the infection has spread beyond the bladder and into the kidneys, other parts of the urinary tract, or the rest of the body.

Learn more about kidney infections vs. UTIs.

The duration of a fever with a UTI can vary depending on several factors, including the severity of the infection and the individual’s overall health.

A person’s fever should resolve within a few days after taking broad-spectrum antibiotics. This is an antibiotic that works against many types of bacteria. If symptoms do not improve by then, a person needs to contact the doctor.

If an individual does not receive treatment or if the infection is particularly severe, the fever may persist for a longer period. At this point, there is a risk of complications.

Learn more about breaking a fever.

People need to consult a doctor if symptoms are very uncomfortable or last for more than 5 days, especially if fever is present.

While mild UTIs may resolve on their own with plenty of fluids and rest, more severe infections require prompt medical intervention to prevent complications such as kidney damage or bloodstream infection.

Individuals also need to speak with a doctor if they experience the following:

  • a high temperature or fever of 100.4ºF (38ºC) or above
  • a sudden worsening of symptoms
  • pain in the sides or back
  • shivering and chills
  • nausea or vomiting
  • confusion
  • agitation or restlessness

If a person is pregnant, has an underlying health condition, or has a history of recurrent UTIs, they should consult a healthcare professional when fever develops.

To treat a UTI, a doctor usually prescribes a course of antibiotics that the person can take at home. Treating the underlying cause can also help with the fever.

The course usually starts with an antibiotic that treats the most common bacteria that would cause UTI. Bacteria within the genitalia area are likely to be the cause. Urine cultures — a type of lab test — can help determine the specific bacteria causing infection and treat it accordingly.

Completing the full course of antibiotics, even if a person’s symptoms improve before then, is vital. This ensures that the infection has fully gone.

A doctor may also recommend over-the-counter pain medication to help with uncomfortable UTI symptoms and help reduce fever. Frequently drinking plenty of water and peeing can also help flush out bacteria from the urinary tract and promote healing.

If an upper UTI is more serious or there is a higher risk of complications, individuals may need hospital treatment.

Learn more about treating UTIs.

Below are answers to common questions about UTIs.

What are the three main symptoms of UTI?

The three main symptoms of UTI include a frequent urge to pee, a burning sensation during urination, and cloudy or strong-smelling urine.

Is it typical to have a fever with a UTI?

While not everyone with a UTI experiences it, fever is likely to accompany more severe infections, such as an upper UTI, and if the infection has spread to the kidneys.

Can a UTI give you flu-like symptoms?

In some cases, UTIs can cause symptoms that resemble those of the flu, such as fever, chills, and fatigue. These symptoms can indicate a more severe infection, and a person needs to speak with a healthcare professional for evaluation and treatment.

How do you know if a UTI has spread to your kidneys?

Symptoms that may indicate a UTI has spread to the kidneys include fever, chills, back or side pain, nausea, and vomiting. If an individual experiences any of these symptoms, they need to seek medical attention. This can help prevent serious complications.

While not all urinary tract infections (UTIs) result in fever, they can be a symptom of more severe infections, such as an upper UTI or the spread of infection to the kidneys.

If an individual experiences fever with a UTI or other UTI symptoms, they need to seek medical attention. A doctor may recommend antibiotics and advise the person to drink plenty of fluids.

With timely intervention and proper management, treatment for most UTIs can be effective, preventing complications such as kidney infection.