Norfloxacin

1 medicine

Norfloxacin is a fluoroquinolone antibiotic used mainly for urinary tract infections. It carries boxed warnings for tendon rupture, aortic aneurysm or dissection, and nerve damage.

Noroxin

Norfloxacin

400mg

Noroxin is a antibiotics medication containing Norfloxacin, available as 400mg tablets.

from $0.70 / tablet View

Key facts

  • Norfloxacin (an ingredient in Noroxin) is a fluoroquinolone antibiotic that stops bacteria from copying their DNA. It is used mainly for urinary tract infections when other antibiotics are unsuitable.
  • Tablets are usually taken twice daily on an empty stomach, well away from dairy, antacids, or mineral supplements, which block its absorption.
  • Fluoroquinolones like norfloxacin carry warnings for tendon rupture, aortic aneurysm or dissection, and permanent nerve damage. These risks are why norfloxacin is now reserved for infections that cannot be treated with a safer antibiotic.
  • Seek urgent care for sudden tendon pain or swelling, tearing chest, back, or abdominal pain, or new tingling and numbness.

What norfloxacin treats

Norfloxacin treats bacterial urinary tract and prostate infections caused by susceptible organisms. It is not a first-choice antibiotic for cough, sore throat, or minor skin infections, and resistance has made it unreliable for gonorrhoea and traveller's diarrhoea in many regions. A prescriber selects it only when the infecting bacteria are known or likely to respond and other options are not appropriate.

How norfloxacin works

Norfloxacin blocks two bacterial enzymes, DNA gyrase and topoisomerase IV, that bacteria need to copy and repair their DNA. Without working DNA, susceptible bacteria cannot multiply and are cleared by the immune system.

Before you take it

  • Avoid norfloxacin if you have a history of tendon problems with a fluoroquinolone, myasthenia gravis, or a known aortic aneurysm.
  • Tell your prescriber about corticosteroid use, kidney disease, heart transplant, or a family history of aortic aneurysm, all of which raise the risk of serious side effects.
  • It is not routinely recommended in pregnancy, while breastfeeding, or in children, because of the risk to developing joints.
  • Separate doses from dairy products, calcium, iron, zinc, and antacids by at least 2 hours, and drink plenty of water during treatment.

Side effects

Common effects include nausea, diarrhoea, headache, and dizziness.

Stop and seek urgent medical care for any of these:

  • Sudden tendon pain, swelling, or difficulty moving a joint, especially the Achilles tendon.
  • Tearing pain in the chest, back, or abdomen (possible aortic tear).
  • New tingling, numbness, or weakness in the arms or legs.
  • Confusion, hallucinations, seizures, or severe mood changes.

Safety essentials

  • Norfloxacin carries boxed warnings for tendon rupture, aortic aneurysm and dissection, and irreversible peripheral neuropathy; stop the antibiotic immediately and contact a doctor if any of these symptoms appear, rather than waiting for the course to finish.
  • It is contraindicated in people with myasthenia gravis, since it can worsen muscle weakness and trigger breathing difficulty.
  • Finish the prescribed course unless a doctor tells you to stop, but do not continue or restart it if you develop tendon or nerve symptoms.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.