Men get urinary tract infections when bacteria enter the urethra and travel up into the bladder, prostate, or kidneys. It’s far less common in men than women, mostly because the male urethra is about 20 cm (roughly 8 inches) long, compared to only 3 to 4 cm in women. That extra distance makes it much harder for bacteria to reach the bladder. But several conditions and behaviors can overcome that natural protection.
Why the Male Urinary Tract Is Usually Protected
The length of the urethra is the biggest reason men rarely get UTIs, especially younger men. Bacteria that enter the urethral opening have to travel a long way before they reach the bladder, and the regular flow of urine flushes most of them out before they can establish an infection. The prostate gland also produces antimicrobial substances that help neutralize bacteria along the way.
This protection isn’t foolproof, though. Anything that slows urine flow, introduces bacteria deeper into the tract, or weakens the immune system can tip the balance.
An Enlarged Prostate Is the Most Common Cause
In men over 50, an enlarged prostate is the leading reason UTIs develop. The prostate sits directly beneath the bladder, and the urethra runs through the center of it. When the prostate grows larger, it squeezes the urethra and partially blocks urine flow. That means the bladder doesn’t fully empty each time you urinate, and the leftover urine becomes a breeding ground for bacteria.
This type of incomplete emptying is called urinary retention, and it creates a warm, stagnant environment where bacteria multiply quickly. Men with prostate enlargement who get one UTI often get repeated infections until the underlying retention problem is addressed.
Kidney Stones and Other Blockages
Kidney stones can block the ureter, the tube connecting the kidney to the bladder, causing urine to back up. That stagnant urine raises infection risk the same way an enlarged prostate does. Large stones are particularly problematic because they can trap bacteria and make infections harder to treat. Some types of kidney stones, called struvite stones, are actually caused by bacterial infections themselves, creating a cycle where infection and stone formation feed each other.
Any structural abnormality in the urinary tract, whether from birth, surgery, or injury, can create pockets where urine pools and bacteria thrive.
Catheters and Medical Procedures
A urinary catheter is one of the most direct routes for bacteria to enter the bladder. The tube bypasses all the natural defenses of the urethra and gives bacteria a surface to cling to. The longer a catheter stays in place, the higher the infection risk. Men who’ve had recent urological procedures, cystoscopy (a camera inserted into the bladder), or prostate surgery also face temporarily elevated risk because instruments can introduce bacteria or cause minor tissue damage that makes infection easier to establish.
Sexual Activity and Circumcision Status
Sex can push bacteria into the urethra. Anal intercourse carries a higher risk because it exposes the urethra to intestinal bacteria, the same organisms responsible for most UTIs. Being uncircumcised also increases risk. The foreskin can harbor bacteria that are more easily introduced into the urethral opening during sexual activity.
Urinating shortly after sex helps flush out any bacteria that may have entered the urethra before they can travel upward.
Which Bacteria Are Responsible
E. coli, the same gut bacterium that causes the vast majority of UTIs in women, is responsible for about 25% of male UTIs. That’s a lower share than in women because men’s infections are more varied. Proteus and Providencia bacteria account for a large portion of the remaining cases, with Klebsiella, Pseudomonas, and enterococci showing up less frequently.
When a UTI involves the prostate specifically (a condition called bacterial prostatitis), E. coli dominates again, causing roughly 80% of cases. Prostate infections are particularly stubborn because antibiotics have a harder time penetrating prostate tissue, which is why these infections tend to recur.
Symptoms in Men
The symptoms overlap with what women experience but can also involve the prostate. Common signs include a burning sensation during urination, a frequent or urgent need to urinate (often producing only small amounts), cloudy or strong-smelling urine, and pain in the lower abdomen or pelvis. Blood in the urine is possible.
If the infection spreads to the kidneys, you may develop fever, chills, nausea, and pain in the back or side. Prostate involvement often adds deep pelvic pain, difficulty starting urination, and sometimes pain during ejaculation.
How Male UTIs Are Diagnosed and Treated
Because UTIs are uncommon in men, doctors typically take them more seriously than a straightforward bladder infection in a woman. A urine culture is almost always ordered to identify the specific bacteria and determine which antibiotics will work. This matters because male UTIs involve a wider range of bacterial species, and picking the wrong antibiotic wastes time and can worsen the infection.
Updated guidelines from the Infectious Diseases Society of America no longer automatically classify every male UTI as “complicated” just because the patient is male. Instead, doctors now focus on whether you have fever, abnormal vital signs, or a catheter to determine how aggressively to treat. A simple bladder infection without fever may need only a short course of oral antibiotics, while an infection with systemic symptoms or prostate involvement typically requires a longer course, sometimes four to six weeks.
If you get more than one UTI, your doctor will likely look for an underlying cause: prostate enlargement, kidney stones, or a structural abnormality in the urinary tract.
Reducing Your Risk
Staying well hydrated is the simplest prevention strategy. Drinking plenty of water keeps urine flowing and flushes bacteria before they can establish themselves. Urinating regularly rather than holding it for long periods keeps the bladder relatively empty and inhospitable to bacterial growth. Urinating after sex is particularly helpful for clearing any bacteria introduced during intercourse.
For men with recurrent infections, doctors may prescribe a low-dose antibiotic taken daily for three months to a year, or a single dose after sexual activity if that’s when infections tend to occur. Cranberry extract supplements show some evidence of helping prevent E. coli from attaching to the bladder wall, though the effect is modest. Addressing the root cause, whether that’s treating an enlarged prostate, removing kidney stones, or managing a catheter more carefully, is the most effective long-term solution.