Uncomplicated infections can be diagnosed and treated based on symptoms alone. Antibiotics taken by mouth such as trimethoprim/sulfamethoxazole (TMP/SMX), nitrofurantoin, or fosfomycin are typically first line. Cephalosporins, amoxicillin/clavulanic acid, or a fluoroquinolone may also be used. However, resistance to fluoroquinolones among the bacterial that cause urinary infections has been increasing. The FDA recommends against the use of fluoroquinolones when other options are available due to higher risks of serious side effects. These medications substantially shorten the time to recovery with all being equally effective. A three-day treatment with trimethoprim, TMP/SMX, or a fluoroquinolone is usually sufficient, whereas nitrofurantoin requires 5–7 days. Fosfomycin may be used as a single dose but has been associated with lower rates of efficacy.

With treatment, symptoms should improve within 36 hours. About 50% of people will recover without treatment within a few days or weeks. Fluoroquinolones are not recommended as a first treatment. The Infectious Diseases Society of America states this due to the concern of generating resistance to this class of medication. Amoxicillin-clavulanate appears less effective than other options. Despite this precaution, some resistance has developed to all of these medications related to their widespread use. Trimethoprim alone is deemed to be equivalent to TMP/SMX in some countries. For simple UTIs, children often respond to a three-day course of antibiotics. Women with recurrent simple UTIs may benefit from self-treatment upon occurrence of symptoms with medical follow-up only if the initial treatment fails.

The mainstay of treatment is antibiotics. Phenazopyridine is occasionally prescribed during the first few days in addition to antibiotics to help with the burning and urgency sometimes felt during a bladder infection. However, it is not routinely recommended due to safety concerns with its use, specifically an elevated risk of methemoglobinemia (higher than normal level of methemoglobin in the blood). Acetaminophen (paracetamol) may be used for fevers. There is no good evidence for the use of cranberry products for treating current infections.

Symptomatic bacteriuria is typically treated as a urinary tract infection with antibiotics. Common choices include nitrofurantoin, and trimethoprim/sulfamethoxazole.

Asymptomatic bacteriuria generally does not require treatment. Exceptions include during pregnancy and in those undergoing surgery of the urinary tract. Children with vesicoureteral reflux or others with structural abnormalities of the urinary tract.

There is no indication to treat asymptomatic bacteriuria in diabetics, renal transplant recipients, and in those with spinal cord injuries.

The overuse of antibiotic therapy to treat asymptomatic bacteriuria increases the risk of diarrhea, antimicrobial resistance, and infection due to Clostridium difficile. Other effects include increased financial burdens and overreporting of mandated catheter-associated urinary tract infection.

People with acute pyelonephritis that is accompanied by high fever and leukocytosis are typically admitted to the hospital for intravenous hydration and intravenous antibiotic treatment. Treatment is typically initiated with an intravenous fluoroquinolone, an aminoglycoside, an extended-spectrum penicillin or cephalosporin, or a carbapenem. Combination antibiotic therapy is often used in such situations. The treatment regimen is selected based on local resistance data and the susceptibility profile of the specific infecting organism(s).

During the course of antibiotic treatment, serial white blood cell count and temperature are closely monitored. Typically, the intravenous antibiotics are continued until the person has no fever for at least 24 to 48 hours, then equivalent antibiotics by mouth can be given for a total of 2–week duration of treatment. Intravenous fluids may be administered to compensate for the reduced oral intake, insensible losses (due to the raised temperature) and vasodilation and to optimize urine output. Percutaneous nephrostomy or ureteral stent placement may be indicated to relieve obstruction caused by a stone. Children with acute pyelonephritis can be treated effectively with oral antibiotics (cefixime, ceftibuten and amoxicillin/clavulanic acid) or with short courses (2 to 4 days) of intravenous therapy followed by oral therapy. If intravenous therapy is chosen, single daily dosing with aminoglycosides is safe and effective.

Treatment of xanthogranulomatous pyelonephritis involves antibiotics as well as surgery. Removal of the kidney is the best surgical treatment in the overwhelming majority of cases, although polar resection (partial nephrectomy) has been effective for some people with localized disease. Watchful waiting with serial imaging may be appropriate in rare circumstances.

In people who do not require hospitalization and live in an area where there is a low prevalence of antibiotic-resistant bacteria, an fluoroquinolone by mouth such as ciprofloxacin or levofloxacin is an appropriate initial choice for therapy. In areas where there is a higher prevalence of fluoroquinolone resistance, it is useful to initiate treatment with a single intravenous dose of a long-acting antibiotic such as ceftriaxone or an aminoglycoside, and then continuing treatment with a fluoroquinolone. Oral trimethoprim/sulfamethoxazole is an appropriate choice for therapy if the bacteria is known to be susceptible. If trimethoprim/sulfamethoxazole is used when the susceptibility is not known, it is useful to initiate treatment with a single intravenous dose of a long-acting antibiotic such as ceftriaxone or an aminoglycoside. Oral beta-lactam antibiotics are less effective than other available agents for treatment of pyelonephritis. Improvement is expected in 48 to 72 hours.

Unfortunately mesna is ineffective as a treatment once hemorrhagic cystitis has developed. Although rare, once a case of radiation-induced hemorrhagic cystitis is diagnosed there is no empirically-proven treatments to heal this type of condition, which can severely degrade a patient's quality of life and might possibly lead to renal failure with risk of death.

Viral hemorrhagic cystitis in children generally spontaneously resolves within a few days.

The first step in the treatment of HC should be directed toward clot evacuation. Bladder outlet obstruction from clots can lead to urosepsis, bladder rupture, and renal failure. Clot evacuation can be performed by placing a wide-lumen bladder catheter at bedside. The bladder can be irrigated with water or sodium chloride solution. The use of water is preferable because water can help with clot lysis. Care must be taken to not overdistend the bladder and cause a perforation.. Hyperbaric oxygen (HBO2) therapy has been proven to be effective in treating radiation-induced hemorrhagic cystitis.

Antibiotics are the first line of treatment in acute prostatitis. Antibiotics usually resolve acute prostatitis infections in a very short time, however a minimum of two to four weeks of therapy is recommended to eradicate the offending organism completely. Appropriate antibiotics should be used, based on the microbe causing the infection. Some antibiotics have very poor penetration of the prostatic capsule, others, such as ciprofloxacin, trimethoprim/sulfamethoxazole, and tetracyclines such as doxycycline penetrate prostatic tissue well. In acute prostatitis, penetration of the prostate is not as important as for category II because the intense inflammation disrupts the prostate-blood barrier. It is more important to choose a bactericidal antibiotic (kills bacteria, e.g., a fluoroquinolone antibiotic) rather than a bacteriostatic antibiotic (slows bacterial growth, e.g. tetracycline) for acute potentially life-threatening infections.

Severely ill patients may need hospitalization, while nontoxic patients can be treated at home with bed rest, analgesics, stool softeners, and hydration. Men with acute prostatitis complicated by urinary retention are best managed with a suprapubic catheter or intermittent catheterization. Lack of clinical response to antibiotics should raise the suspicion of an abscess and prompt an imaging study such as a transrectal ultrasound (TRUS).

Urinary catheters should be inserted using aseptic technique and sterile equipment (including sterile gloves, drape, sponges, antiseptic and sterile solution), particularly in an acute care setting. Hands should be washed before and after catheter insertion. Overall, catheter use should be minimized in all patients, particularly those at higher risk of CAUTI and mortality (e.g. the elderly or those with impaired immunity).

Diet modification is often recommended as a first-line method of self-treatment for interstitial cystitis, though rigorous controlled studies examining the impact diet has on interstitial cystitis signs and symptoms are currently lacking. Individuals with interstitial cystitis often experience an increase in symptoms when they consume certain foods and beverages. Avoidance of these potential trigger foods and beverages such as caffeine-containing beverages including coffee, tea, and soda, alcoholic beverages, chocolate, citrus fruits, hot peppers, and artificial sweeteners may be helpful in alleviating symptoms. Diet triggers vary between individuals with IC; the best way for a person to discover his or her own triggers is to use an elimination diet. Sensitivity to trigger foods may be reduced if calcium glycerophosphate and/or sodium bicarbonate is consumed. The foundation of therapy is a modification of diet to help patients avoid those foods which can further irritate the damaged bladder wall.

The mechanism by which dietary modification benefits people with IC is unclear. Integration of neural signals from pelvic organs may mediate the effects of diet on symptoms of IC.

Bladder instillation of medication is one of the main forms of treatment of interstitial cystitis, but evidence for its effectiveness is currently limited. Advantages of this treatment approach include direct contact of the medication with the bladder and low systemic side effects due to poor absorption of the medication. Single medications or a mixture of medications are commonly used in bladder instillation preparations. DMSO is the only approved bladder instillation for IC/BPS yet it is much less frequently used in urology clinics.

A 50% solution of DMSO had the potential to create irreversible muscle contraction. However, a lesser solution of 25% was found to be reversible. Long-term use of DMSO is questionable, as its mechanism of action is not fully understood though DMSO is thought to inhibit mast cells and may have anti-inflammatory, muscle-relaxing, and analgesic effects. Other agents used for bladder instillations to treat interstitial cystitis include: heparin, lidocaine, chondroitin sulfate, hyaluronic acid, pentosan polysulfate, oxybutynin, and botulinum toxin A. Preliminary evidence suggests these agents are efficacious in reducing symptoms of interstitial cystitis, but further study with larger, randomized, controlled clinical trials is needed.

Antibiotic therapy has to overcome the blood/prostate barrier that prevents many antibiotics from reaching levels that are higher than minimum inhibitory concentration. A blood-prostate barrier restricts cell and molecular movement across the rat ventral prostate epithelium. Treatment requires prolonged courses (4–8 weeks) of antibiotics that penetrate the prostate well. The fluoroquinolones, tetracyclines and macrolides have the best penetration. There have been contradictory findings regarding the penetrability of nitrofurantoin , quinolones (ciprofloxacin, levofloxacin), sulfas (Bactrim, Septra), doxycycline and macrolides (erythromycin, clarithromycin). This is particularly true for gram-positive infections.

In a review of multiple studies, Levofloxacin (Levaquin) was found to reach prostatic fluid concentrations 5.5 times higher than Ciprofloxacin, indicating a greater ability to penetrate the prostate.

Persistent infections may be helped in 80% of patients by the use of alpha blockers (tamsulosin (Flomax), alfuzosin), or long term low dose antibiotic therapy. Recurrent infections may be caused by inefficient urination (benign prostatic hypertrophy, neurogenic bladder), prostatic stones or a structural abnormality that acts as a reservoir for infection.

In theory, the ability of some strains of bacteria to form biofilms might be one factor amongst others to facilitate development of chronic bacterial prostatitis.

Escherichia coli extract and cranberry have a potentially preventive effect on the development of chronic bacterial prostatitis, while combining antibiotics with saw palmetto, lactobacillus sporogens and arbutin may lead to better treatment outcomes.

Bacteriophages hold promise as another potential treatment for chronic bacterial prostatatis.

The addition of prostate massage to courses of antibiotics was previously proposed as being beneficial and prostate massage may mechanically break up the biofilm and enhance the drainage of the prostate gland. However, in more recent trials, this was not shown to improve outcome compared to antibiotics alone.

Over time, the relapse rate is high, exceeding 50%. However, recent research indicates that combination therapies offer a better prognosis than antibiotics alone.

A 2007 study showed that repeated combination pharmacological therapy with antibacterial agents (ciprofloxacin/azithromycin), alpha-blockers (alfuzosin) and Serenoa repens extracts may eradicate infection in 83.9% of patients with clinical remission extending throughout a follow-up period of 30 months for 94% of these patients.

A 2014 study of 210 patients randomized into two treatment groups found that recurrence occurred within 2 months in 27.6% of the group using antibiotics alone (prulifloxacin 600 mg), but in only 7.8% of the group taking prulifloxacin in combination with Serenoa repens extract, Lactobacillus Sporogens and Arbutin.

Neonatal infection treatment is typically started before the diagnosis of the cause can be confirmed.

Neonatal infection can be prophylactically treated with antibiotics. Maternal treatment with antibiotics is primarily used to protect against group B streptococcus.

Women with a history of HSV, can be treated with antiviral drugs to prevent symptomatic lesions and viral shedding that could infect the infant at birth. The antiviral medications used include acyclovir, penciclovir, valacyclovir, and famciclovir. Only very small amounts of the drug can be detected in the fetus. There are no increases in drug-related abnormalities in the infant that could be attributed to acyclovir. Long-term effects of antiviral medications have not been evaluated for their effects after growth and development of the child occurs. Neutropenia can be a complication of acyclovir treatment of neonatal HSV infection, but is usually transient. Treatment with immunoglobulin therapy has not been proven to be effective.

Medical treatment entails low dose antibiotic prophylaxis until resolution of VUR occurs. Antibiotics are administered nightly at half the normal therapeutic dose. The specific antibiotics used differ with the age of the patient and include:

- Amoxicillin or ampicillin – infants younger than 6 weeks

- Trimethoprim-sulfamethoxazole (co-trimoxazole) – 6 weeks to 2 months

After 2 months the following antibiotics are suitable:

- Nitrofurantoin {5–7 mg/kg/24hrs}

- Nalidixic acid

- Bactrim

- Trimethoprim

- Cephalosporins

Urine cultures are performed 3 monthly to exclude breakthrough infection. Annual radiological investigations are likewise indicated. Good perineal hygiene, and timed and double voiding are also important aspects of medical treatment. Bladder dysfunction is treated with the administration of anticholinergics.

Even when caught early, aggressive treatment is required (Bobba). Antibiotics are proven to cure Emphysematous cystitis over time and reduce the amount of gas inside the bladder wall. Prognosis is poor if antibiotics are not used to treat the patient. Additional treatment consists of urinary drainage and good control of blood glucose. The treatment of underlying comorbid diseases, such as diabetes, is extremely important because they can intensify the infection (Gheonea, Bondari). Hyperbaric oxygen is an effective treatment, and has cured some cases in as little as 48 hours. Although it is unclear as to how gas formation occurs in emphysematous cystitis, it’s dependant on whether or not the patient has contributing diseases (Mccabe). Gas formation in diabetic patients diagnosed with Emphysematous cystitis has been determined to occur due to the production of carbon dioxide as a result of the fermentation of the high concentrations of glucose. Gas formation in nondiabetic patients is most likely due the breaking down of urinary lactulose and tissue proteins. Inflammation caused by infection increases pressure and decreases circulation, which provides the perfect environment for bacteria to produce gas (Sereno).

A variety of drugs may be prescribed based on the cause of the patient's urethritis. Some examples of medications based on causes include: azithromycin, doxycycline, erythromycin, levofloxacin, metronidazole, ofloxacin, or tinidazole.

Proper perineal hygiene should be stressed. This includes avoiding use of vaginal deodorant sprays and proper wiping after urination and bowel movements. Intercourse should be avoided until symptoms subside.

Endoscopic injection involves applying a gel around the ureteral opening to create a valve function and stop urine from flowing back up the ureter. The gel consists of two types of sugar-based molecules called dextranomer and hyaluronic acid. Trade names for this combination include Deflux and Zuidex. Both constituents are well-known from previous uses in medicine. They are also biocompatible, which means that they do not cause significant reactions within the body. In fact, hyaluronic acid is produced and found naturally within the body.

When in acute urinary retention, treatment of the urethral stricture or diversion is an emergency. Options include:

- Urethral dilatation and catheter placement. This can be performed in the Emergency Department, a practitioner's office or an operating room. The advantage of this approach is that the urethra may remain patent for a period of time after the dilation, though long-term success rates are low.

- Insertion of a suprapubic catheter with catheter drainage system. This procedure is performed in an Operating Room, Emergency Department or practitioner's office. The advantage of this approach is that it does not disrupt the scar and interfere with future definitive surgery.

Among the categories of bacteria most known to infect patients are the category MRSA (resistant strain of "S. aureus"), member of gram-positive bacteria and "Acinetobacter" ("A. baumannii"), which is gram-negative. While antibiotic drugs to treat diseases caused by gram-positive MRSA are available, few effective drugs are available for "Acinetobacter". "Acinetobacter" bacteria are evolving and becoming immune to existing antibiotics, so in many cases, polymyxin-type antibacterials need to be used. "In many respects it’s far worse than MRSA," said a specialist at Case Western Reserve University.

Another growing disease, especially prevalent in New York City hospitals, is the drug-resistant, gram-negative "Klebsiella pneumoniae". An estimated more than 20% of the "Klebsiella" infections in Brooklyn hospitals "are now resistant to virtually all modern antibiotics, and those supergerms are now spreading worldwide."

The bacteria, classified as gram-negative because of their reaction to the Gram stain test, can cause severe pneumonia and infections of the urinary tract, bloodstream, and other parts of the body. Their cell structures make them more difficult to attack with antibiotics than gram-positive organisms like MRSA. In some cases, antibiotic resistance is spreading to gram-negative bacteria that can infect people outside the hospital. "For gram-positives we need better drugs; for gram-negatives we need any drugs," said Dr. Brad Spellberg, an infectious-disease specialist at Harbor-UCLA Medical Center, and the author of "Rising Plague", a book about drug-resistant pathogens.

One-third of nosocomial infections are considered preventable. The CDC estimates 2 million people in the United States are infected annually by hospital-acquired infections, resulting in 20,000 deaths. The most common nosocomial infections are of the urinary tract, surgical site and various pneumonias.

In a small minority of cases of urethral syndrome, treatment with antibiotics is effective, which indicates that in some cases it may be caused by bacterial infection which does not show up in either urinalysis or urine culture. For chronic urethral syndrome, a long term, low-dose antibiotic treatment is given on a continuous basis or after intercourse each time if intercourse appears to trigger symptoms.

As low oestrogen may also be considered a source for urethral syndrome, hormone replacement therapy, and oral contraceptive pill (birth-control pills) containing oestrogen are also used to treat the symptoms of this condition in women.

Following urethroplasty, patients should be monitored for a minimum of 1 year, since the vast majority of recurrences occur within 1 year.

Because of the high rate of recurrence following dilation and other endoscopic approaches, the provider must maintain a high index of suspicion for recurrence when the patient presents with obstructive voiding symptoms or urinary tract infection.

The methods used differ from country to country (definitions used, type of nosocomial infections covered, health units surveyed, inclusion or exclusion of imported infections, etc.), so the international comparisons of nosocomial infection rates should be made with the utmost care.

"S. pneumonia" can be treated with a combination of penicillin and ampicillin.

In cases of herpes simplex virus-derived meningitis, antiviral therapy (acyclovir or vidarabine) must be started immediately for a favorable outcome. Acyclovir is a better antiviral because it shows a similar effect on the infection as vidarabine and is safer to use in the neonate. The recommended dosage is 20 mg/kg every six hours for 21 days.