Men get urinary tract infections when bacteria enter the urethra and travel upward into the bladder, prostate, or kidneys. It happens far less often than in women, largely because the male urethra is significantly longer, creating a greater distance bacteria must travel to reach the bladder. Prostate secretions also have natural antibacterial properties that kill many organisms before they can establish an infection. Still, certain conditions and behaviors override those built-in defenses.
Why Men Are Less Prone but Not Immune
In women, the short distance between the urethral opening and the bladder, combined with the proximity of the urethra to the anus and vagina, makes bacterial entry relatively easy. In men, the urethral opening sits at the tip of the penis, much farther from the bladder. That extra distance alone stops most bacteria from completing the journey. The prostate gland, which wraps around the urethra just below the bladder, adds another layer of protection by producing fluid that kills bacteria.
These advantages aren’t absolute. Once bacteria do gain a foothold, male UTIs tend to be classified as complicated infections because there’s usually an underlying reason the normal defenses failed. That’s why a UTI in a man almost always prompts a doctor to look for a contributing cause rather than simply prescribing antibiotics and moving on.
The Most Common Causes in Men
Enlarged Prostate
An enlarged prostate, or benign prostatic hyperplasia, is one of the most frequent reasons men develop UTIs, especially after age 50. The prostate sits directly beneath the bladder, and the urethra passes through its center. When the gland grows, it physically squeezes the urethra and restricts urine flow. The result is a bladder that never fully empties. That leftover urine becomes a warm, stagnant environment where bacteria multiply easily. Over time, the chronic pressure can also damage the kidneys or allow bladder infections to spread upward.
Urinary Catheters and Medical Procedures
Any tube or instrument inserted into the urethra can introduce bacteria directly into the urinary tract. Catheterization during hospital stays is one of the leading causes of UTIs in men. The longer a catheter stays in place, the higher the risk. Procedures like cystoscopy, where a camera is threaded into the bladder, carry a similar though smaller risk.
Kidney Stones and Structural Blockages
Kidney stones or other structural abnormalities can block urine flow at various points in the urinary tract. Just like with an enlarged prostate, any obstruction that prevents the bladder from draining completely creates conditions for bacterial growth. Stones can also irritate the lining of the urinary tract, making it easier for bacteria to attach and colonize.
Diabetes
People with diabetes face up to 10 times the risk of developing a UTI compared to those without the condition. The reason goes beyond sugar in the urine. Insulin normally helps regulate natural antimicrobial proteins that protect the urinary tract. In people with diabetes, these protective proteins are suppressed, sometimes to levels two to three times lower than in healthy individuals. When insulin therapy begins, those protective protein levels typically recover, but poorly controlled blood sugar keeps the urinary tract vulnerable.
Sexual Activity
Sex can introduce bacteria into the urethra. Anal intercourse carries a particularly high risk because it exposes the urethra to intestinal bacteria. Having multiple partners, unprotected sex, or a partner with a sexually transmitted infection all increase the likelihood of urethritis, which is infection or inflammation of the urethra itself. This type of infection is technically distinct from a classic UTI, but it involves the same tract and can ascend to the bladder if untreated.
Weakened Immune System
Conditions that suppress the immune system, including HIV, chemotherapy, or long-term steroid use, reduce the body’s ability to fight off bacteria that enter the urinary tract. Men who are immunocompromised are more likely to develop infections from organisms that wouldn’t normally pose a threat.
Which Bacteria Are Responsible
E. coli causes roughly 25% of bladder and kidney infections in men. That’s a notably smaller share than in women, where E. coli dominates about 80% of cases. In men, Proteus and Providencia species account for a large portion of the remaining infections, with Klebsiella, Pseudomonas, and Enterococcus rounding out the list. The broader range of bacterial culprits in men is another reason doctors typically run a urine culture to identify the specific organism rather than guessing.
When infection involves the prostate specifically, E. coli reasserts its dominance, causing about 80% of chronic bacterial prostatitis cases.
Symptoms to Recognize
A UTI in men typically produces a recognizable pattern of symptoms:
- Unusually frequent urination or a sudden, intense urge to go
- Burning or pain during urination
- Cloudy or foul-smelling urine
- Pain or pressure in the lower abdomen, below the navel
- Waking up multiple times at night to urinate
If the infection reaches the kidneys, you may also notice fever, chills, nausea, vomiting, or pain in the side or upper back. These are signs the infection has moved beyond the bladder and needs prompt treatment.
UTI vs. Sexually Transmitted Infection
UTI symptoms in men overlap significantly with urethritis caused by sexually transmitted infections like gonorrhea and chlamydia. Both can produce burning during urination and unusual discharge. The key differences: STI-related urethritis often causes visible discharge from the penis and tends to develop after sexual exposure. A standard UTI more commonly involves urinary frequency, urgency, and lower abdominal discomfort without discharge.
Doctors sort this out through urine testing. A standard UTI will show both white blood cells and bacteria under a microscope, while STI-related infections require specific testing for gonorrhea and chlamydia. Your sexual history, including number of partners and whether you’ve had unprotected or anal intercourse, helps guide which tests are ordered.
How Male UTIs Are Treated
Antibiotics are the standard treatment, but men typically need a longer course than women. Current guidelines recommend 5 to 7 days of treatment for complicated UTIs, which includes most male infections. If a doctor suspects the prostate is involved, treatment often extends to 10 to 14 days because antibiotics penetrate prostate tissue less efficiently.
A urine culture is important in men because the range of possible bacteria is wider, and some organisms are resistant to common first-line antibiotics. Your doctor will often start you on an antibiotic right away, then adjust it once the culture results come back in a day or two.
When a UTI Spreads to the Prostate
One complication unique to men is bacterial prostatitis. Bacteria can travel from the urethra into the prostate gland, causing either an acute or chronic infection. Acute bacterial prostatitis comes on suddenly and hits hard, with high fever, chills, severe pain in the groin or lower back, body aches, and difficulty urinating. Some men develop complete urinary blockage, meaning they cannot urinate at all. This is a medical emergency.
Chronic bacterial prostatitis is more subtle. It often develops after a UTI that was treated but never fully cleared. Symptoms are milder, similar to a low-grade UTI that lingers for months: urinary frequency, mild burning, discomfort in the groin or lower back, and sometimes painful ejaculation. The hallmark is UTIs that keep coming back despite treatment. Chronic bacterial prostatitis is actually the most common cause of recurrent UTIs in men, with E. coli responsible for the majority of cases.
Reducing Your Risk
Staying well hydrated helps flush bacteria from the urinary tract before they can establish an infection. Urinating promptly when you feel the urge, rather than holding it, prevents the kind of stagnation that bacteria thrive in. If you have an enlarged prostate and consistently feel like your bladder isn’t emptying fully, addressing that underlying issue is the most effective way to prevent repeat infections.
Using condoms during sex, particularly anal intercourse, reduces bacterial exposure. If you have diabetes, keeping blood sugar well controlled helps restore the natural antimicrobial defenses in your urinary tract. And if you’ve had a catheter placed during a hospital stay, the shorter the duration, the lower your risk.