Urine infection (cystitis)
Burning when passing urine, needing to go more often, or cloudy urine. Very common, especially in women.
How long does a course usually last?
For cystitis, usually 3 days for women who are not pregnant, and 7 days for men or pregnant women. Kidney infection is different: it needs prompt assessment and a longer course, usually 7 to 14 days depending on the antibiotic.
Your prescriber sets the exact length for you. Finish the course you're given unless a healthcare professional tells you to stop.
Never re-use antibiotics
- Do not re-use this treatment, or take leftover or someone else's antibiotics, unless a healthcare professional has expressly told you to.
- The right antibiotic, dose and length depend on your current infection, which can be different from last time.
- Re-using antibiotics can be ineffective, cause side effects, and drives antibiotic resistance. Return leftovers to any pharmacy for safe disposal.
What the guidance says
NICE recommends a short antibiotic course for most women with cystitis. Men, pregnant women, children and people with fever or flank pain (possible kidney infection) always need prompt assessment, as kidney infection needs a different treatment plan. Drinking enough helps; cranberry products are not a treatment.
Based on NICE guidance — always follow your own prescriber's advice.
Antibiotics sometimes prescribed
When to seek help
If you are getting worse, develop a high fever, feel confused or breathless, or your symptoms are not improving as expected, contact your doctor or call NHS 111. See the warning signs page.