How Do You Know If a Urinary Tract Infection Is Starting? Early Signs, and What to Do About Them

Many people can tell when a UTI is coming on, especially if they’ve had one in the past. That’s very helpful because it means you can catch it early, avoiding a more serious bladder infection and more bothersome symptoms. But if you’ve never had a UTI or aren’t sure, there are a few helpful guidelines that will help you decide if your symptoms might be from a UTI and when to get medical care.

Quiz: Do you have a UTI or a STD/STI?

What does the beginning of a UTI feel like?

At the start of a UTI, milder symptoms may include:

• Burning or stinging sensation during urination

• Feeling like you have to urinate more often than usual

• Urinating a smaller amount than usual

• Unusual odor to urine

• Darker, cloudy, and/or pinkish-tinged urine

• Mild discomfort in your lower abdomen

If you’re experiencing more than one of these symptoms, especially if you’ve recently had sexual intercourse or are prone to getting UTIs, you may be getting one.

How long does it take for a UTI to develop?

It takes about 2 days for a UTI to develop. Once the bacteria enters the urethra (for example, during sex), they start multiplying until the first symptoms of a UTI start. This usually happens in about 48 hours. 

Can you stop a UTI before it starts?

Quite possibly. Even though there’s not a lot of research on the topic, many people swear they can ward off early UTI symptoms by using cranberry products and hydrating well. 

How does cranberry help with UTIs?

The active ingredient in cranberry, PAC, prevents bacteria from sticking to the inside of the bladder wall, according to research. This means the bacteria have less chance to spread and cause infection. Cranberry tablets are more cost effective than cranberry juice, since the tablets have a much higher concentration of the active ingredient. Most cranberry juice preparations contain a lot of extra sugar, since pure cranberry juice tastes very bitter.  

In one small study, cranberry tablets of 500 mg or 1,000 mg taken daily reduced UTI symptoms and bacterial load compared with no treatment. More research has been done on using cranberry products to prevent UTIs rather than to treat them, however. If you’re prone to getting UTIs, it would work better to take cranberry pills regularly before you develop any symptoms. 

Does drinking a lot of water help with UTIs?

As with cranberry pills, drinking plenty of water works better to prevent UTIs than to treat them. 

One randomized controlled trial studied women who were prone to UTIs and didn’t drink a lot of fluids. Some of these women were asked to increase how much fluid they drink, and other women kept drinking their regular (relatively low) amount of fluids. The women who increased their fluid intake got significantly fewer UTIs over the course of the following year than the women who didn’t. 

So it seems that if you generally don’t stay well hydrated, increasing the amount of water you drink can help you avoid UTIs.

“Flushing” out a UTI once it has started by drinking lots of water has been recommended for ages. When you urinate more, it pushes bacteria out of your urinary system and into your urine. However, you don’t want to go overboard, because drinking too much water can be very dangerous.

What other conditions can feel like a UTI?

In addition to UTIs, uncomfortable urinary symptoms can be caused by other medical conditions. Sometimes these overlap with a UTI, so it’s important to get a urine test if you’re not sure what’s causing your symptoms. Some common causes of pain with urination include:

• Sexually transmitted infections

• Yeast infections

• Bacterial vaginosis (in women)

• Interstitial cystitis or painful bladder syndrome

• Inflammation (from soaps, perfumes, or lubricants)

• Prostatitis (in men)

When to get treatment for a UTI

In many cases it’s OK to wait 1 to 2 days to see if your UTI symptoms resolve on their own. However, certain conditions are considered high risk for medical problems. People in these high-risk categories should be evaluated right away for possible UTI symptoms:

• Pregnancy: If you’re pregnant and have signs of a UTI, it’s important to get it checked out right away — unless your only symptom is having to go to the bathroom more frequently, which is a natural part of pregnancy.

• Diabetes or a weakened immune system: Your body can’t fight off infection as well when your immune system isn’t functioning properly. 

• Problems with the urinary tract, such as cysts or kidney stones: Though all the reasons aren’t clear, people who tend to form kidney stones also tend to have more UTIs. 

• Men: Since UTIs aren’t very common in men, any urinary complaints should be evaluated in person, to figure out what’s causing the symptoms. 

In these conditions, it’s especially important to get evaluated in person (not just over telemedicine) so that you can get a urine culture done before starting any antibiotics. An accurate urine culture is very important to make sure these higher-risk conditions are treated with the right antibiotic for the right amount of time.

Women who don’t have a high risk of complications should still get treatment from a healthcare professional if they develop any of the following along with UTI symptoms:

• Fever

• Back pain, especially if it’s worse on one side

• Severe nausea or vomiting

• Visible clots of blood in their urine

• Severe abdominal pain

• Symptoms that aren’t improving or are worsening after 24 to 48 hours of home care 

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Written by:

Nicole Rowe, MD

Dr. Nicole Rowe, MD, is a telehealth family practice physician. She received her medical degree from the University of North Carolina School of Medicine and completed her residency in family medicine at University of Colorado’s Swedish Medical Center.

Edited by:

Katie E. Golden, MD

Katie E. Golden, MD, is a board-certified emergency medicine physician and a medical editor at GoodRx.

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