Urinary infections – recognising one, and when it is serious
Burning and urgency usually mean a bladder infection. Fever and back pain mean it has reached the kidney, which is a different matter entirely.
Bladder versus kidney
A bladder infection — cystitis — causes burning on passing urine, needing to go often and urgently, passing small amounts, lower abdominal discomfort, and cloudy or strong-smelling urine. Uncomfortable, common, and usually straightforward to treat.
When infection travels up to the kidney it adds fever, shivering, pain in the back or side, nausea and vomiting, and a general feeling of being seriously unwell. That is a different illness with a different urgency.
Who should always be seen
- Anyone pregnant — untreated urinary infection in pregnancy can cause premature labour, and it is screened for at antenatal visits for that reason.
- Men, in whom urinary infections are less common and more often signal something else.
- Children, always.
- Anyone with diabetes, kidney disease, a catheter, or a weakened immune system.
- Anyone with repeated infections, which need the cause investigated rather than repeated courses.
Treatment and relief
A confirmed bladder infection is treated with a short antibiotic course. Which one, and for how long, depends on local resistance patterns and on you — this is a clinic decision, and leftover antibiotics from a previous course are a bad idea.
Commonly used in South Africa, on prescription:
Nitrofurantoin — Macrodantin, Urotrim
Uncomplicated lower urinary tract infections (cystitis); UTI prophylaxis
Co-trimoxazole (TMP/SMX) — Bactrim, Purbac, Adco-Trimoxazole
UTIs; PCP pneumonia treatment; toxoplasmosis
Ciprofloxacin — Ciprobay, Ciproxin, Adco-Cipro, Cifloc
UTIs; GI infections; complicated skin infections; typhoid; gonorrhoea
Fosfomycin — Monurol
Uncomplicated urinary tract infection (single dose)
- Drink plenty of water while symptoms last.
- Paracetamol or an anti-inflammatory for the discomfort.
- Urinary alkalinisers from a pharmacy ease burning but do not treat the infection.
- Cranberry has weak evidence for prevention and none for treating an established infection.
Reducing the chances of another
- Drink enough that urine stays pale.
- Do not hold on for long periods when you feel the urge.
- Pass urine after sex, which is one of the better-supported measures.
- Wipe front to back.
- Avoid douches and scented products, which disturb the natural balance.
- After menopause, ask about topical oestrogen — it substantially reduces recurrent infections and is often not offered.
Common questions
- Can a urinary infection clear on its own?
- Some mild bladder infections do, with fluids and time. But the risk of it reaching the kidney is what makes waiting unwise in anyone with fever, in pregnancy, in men, in children or in anyone with a chronic condition.
- Why do I keep getting them?
- Recurrence is common in women and often has no sinister cause, but repeated infections deserve investigation rather than repeated courses — for stones, incomplete bladder emptying, diabetes or, after menopause, tissue changes that respond to treatment.
- Is cloudy urine always an infection?
- No. Dehydration, diet and some medicines change the appearance and smell of urine. Symptoms matter more than appearance, and appearance alone is not a reason for antibiotics.
Sources
- Primary Healthcare Standard Treatment Guidelines and Essential Medicines ListNational Department of Health, South Africa
- Clinical and public health guidanceWorld Health Organization
Last reviewed 4 August 2026.