A urinary tract infection (UTI) is a bacterial infection of the urinary tract. The bladder is most commonly affected (cystitis, bladder infection). Less often, the infection ascends to the kidneys (pyelonephritis, kidney infection) — a more serious illness that typically requires antibiotic treatment.¹
UTIs are among the most common infections overall. Women are considerably more often affected than men — due to the shorter urethra, which gives bacteria easier access to the bladder.¹,²
Current guidelines distinguish between uncomplicated UTIs (in otherwise healthy people without relevant comorbidities) and complicated UTIs (with certain risk factors such as urinary outflow obstruction, immunosuppression, kidney function impairment). This article focuses primarily on uncomplicated cystitis.
2. Symptoms
Bladder infection (cystitis)
Burning or pain when urinating (dysuria) — the leading symptom
Frequent urge to urinate — often only small amounts of urine
Pain or pressure in the lower abdomen
Cloudy or foul-smelling urine
Occasionally blood in the urine (haematuria) — can look alarming but is typically not dangerous in uncomplicated cystitis
Kidney infection (pyelonephritis) — warning signs
Fever and chills
Flank pain (one- or two-sided)
Marked feeling of being unwell, nausea, vomiting
Seek immediate medical evaluation for these signs
For fever, flank pain or marked feeling of being unwell, immediate medical evaluation should occur — pyelonephritis typically requires antibiotic treatment and can lead to complications if left untreated.
3. Causes and risk factors
Pathogen:E. coli causes the large majority of uncomplicated UTIs. The bacteria typically come from the person's own gut and reach the bladder via the urethra.¹
Female sex: women are considerably more often affected — the shorter urethra and proximity to the anus make it easier for bacteria to reach the bladder.
Sexual activity: intercourse can carry bacteria into the urethra. The term honeymoon cystitis describes this association.
Menopause: falling oestrogen levels alter the lining of the urogenital area and can increase susceptibility to UTIs.
Catheter: a urinary catheter substantially increases the risk of infection.
4. Diagnosis
For typical symptoms of uncomplicated cystitis in an otherwise healthy woman, the symptom history is typically sufficient for the diagnosis — a urine culture is usually not necessary.¹
Symptom history: burning when urinating, frequent urge, lower abdominal pain — the combination of typical symptoms is typically diagnostically sufficient.
Urine dipstick test: can give clues (leucocytes, nitrite, blood). However, with typical symptoms it has limited additional value and can give false-negative results.
Urine culture: typically recommended for atypical symptoms, in men, with recurrent infections, when pyelonephritis is suspected, or with treatment failure.
Imaging: typically not necessary for uncomplicated cystitis. Ultrasound when urinary outflow obstruction or complicated infection is suspected.
5. Treatment: with or without antibiotics?
One of the most important updates in current guidelines: for uncomplicated cystitis in women, a symptomatic treatment without antibiotics can be considered first under certain conditions — with pain medications and adequate fluids. Background: many uncomplicated UTIs resolve without antibiotics.¹
Option 1Symptomatic treatment (non-antibiotic)
Pain medications (e.g. ibuprofen) can relieve symptoms while the infection resolves on its own
Drink plenty of fluids — flushes out bacteria
Warmth (hot water bottle on the lower abdomen)
Conditions: uncomplicated cystitis in an otherwise healthy woman, mild to moderate symptoms, no signs of pyelonephritis.
Option 2Antibiotic treatment
Typically recommended for severe symptoms, lack of response to symptomatic treatment, pyelonephritis, in men and with complicating factors. Antibiotic choice depends on current resistance data and individual circumstances.¹
Uncomplicated cystitis (first line)
Nitrofurantoin and fosfomycin (single dose) are typically among the recommended first-line antibiotics. Other options include pivmecillinam and nitroxoline (regional availability varies).¹
Pyelonephritis
Typically requires a more potent antibiotic and a longer treatment duration. The choice depends on local resistance data.
Fluoroquinolones no longer first choice for uncomplicated cystitis
Fluoroquinolones (e.g. ciprofloxacin) should typically no longer be used for uncomplicated cystitis — due to their side-effect profile (including tendon ruptures, nerve damage) and resistance development. There are more effective and safer alternatives.¹
Herbal remedies
Preparations with bearberry leaves, nasturtium/horseradish or cranberry are often used. The evidence base is limited for some of these and somewhat better for others — they can typically serve as an add-on, but not as a replacement for antibiotic therapy when symptoms are severe.
6. Kidney infection (pyelonephritis)
A pyelonephritis (kidney infection) develops when bacteria ascend from the bladder to the kidneys. It typically presents with fever, flank pain and marked feeling of being unwell — in addition to the bladder infection symptoms.¹
Pyelonephritis typically requires antibiotic treatment. For severe cases, hospital admission may be necessary. Untreated, pyelonephritis can lead to serious complications (including urosepsis).
7. Recurrent UTIs
Recurrent UTIs are typically defined as three or more infections per year. Recurrence prevention is an important part of guidelines.¹
Behavioural measures — drink plenty of fluids, urinate regularly, urinate after intercourse
Vaginal oestrogen in menopause — can substantially reduce frequency
Immunoprophylaxis — oral immunostimulation (e.g. OM-89/Uro-Vaxom) is mentioned in guidelines as an option
D-mannose — some studies show it can reduce recurrence frequency; increasingly recommended
Cranberry products — evidence is mixed, but some studies show a positive effect
Long-term antibiotic prophylaxis — considered as a last option when other measures are insufficient
8. Prevention
Drink plenty of fluids — regular flushing of the urinary tract
Urinate regularly — do not hold urine unnecessarily long
Urinate after intercourse
Intimate hygiene: wipe from front to back — no excessive hygiene in the intimate area (no vaginal douches, no perfumed products)
Avoid getting cold — the evidence is limited, but many affected people report a connection
How brite helps you with UTIs
Finishing the antibiotic course properly even when symptoms are gone after two days. Taking prophylaxis reliably for recurrent infections. And being able to show at the next appointment exactly how often it happened over the past year. That's what brite is for.
Intake reminder — finishing antibiotic courses completely, taking D-mannose or other prophylaxis regularly: brite reminds you on time. Especially with short antibiotic courses, completing the dose matters to prevent resistance.
Drug interaction check — antibiotic plus the pill (which can affect contraceptive reliability)? Plus thyroid medication? Plus a stomach acid medication? brite shows when to take what and what fits together.
Health journal — track frequency of infections, symptoms, antibiotics used and prevention measures over time. So at the next appointment it's easy to show whether the threshold for recurrent UTIs has been reached and what prophylaxis would make sense.
Digital medication plan — all medications clearly organised for urology, gynaecology and GP. Particularly helpful when multiple practices are involved or when an emergency standby antibiotic has been prescribed.
Not necessarily. Current guidelines allow for a trial of symptomatic treatment (pain medication, fluids) for uncomplicated cystitis in otherwise healthy women with mild to moderate symptoms. For severe symptoms, lack of improvement or pyelonephritis, an antibiotic is typically required.¹
The main reason is the shorter urethra in women, which gives bacteria easier access to the bladder. Also, the urethral opening is closer to the anus, where intestinal bacteria (mainly E. coli) are found.
The evidence is mixed. Some studies show a modest protective effect against recurrent UTIs. Cranberry products can be a useful addition but typically do not replace guideline-based treatment or prophylaxis.
A simple sugar that can inhibit the attachment of E. coli bacteria to the bladder lining. Some studies show a positive effect on the recurrence rate. It is increasingly recommended as prophylaxis — the evidence base is growing.
For fever, flank pain, marked illness (suspected pyelonephritis), blood in urine without a clear cause, UTIs in men, lack of improvement after a few days of symptomatic treatment, or more than three infections per year.
Fluoroquinolones (e.g. ciprofloxacin, levofloxacin) are typically no longer first choice for uncomplicated cystitis. They can cause serious side effects (including tendon ruptures, nerve damage) and promote resistance. There are more effective and safer alternatives.¹
Yes, but much less often. UTIs in men should typically always be evaluated medically, as complicating factors are more often present (e.g. enlarged prostate).
Yes — adequate fluid intake helps flush bacteria from the bladder. It is one of the simplest and most effective measures both for treatment and for prevention.
Medical disclaimer: This article is for general information only and does not replace medical advice, diagnosis or treatment. For fever, flank pain or marked feeling of being unwell, immediate medical evaluation should occur. Antibiotics should typically not be taken or stopped on your own. Medication choice is always determined individually. Last updated: April 2026.
