A fluoroquinolone antibiotic
Ofloxacin
A fluoroquinolone antibiotic now reserved for specific infections because of important safety warnings.
What is Ofloxacin?
Ofloxacin is a broad-spectrum fluoroquinolone antibiotic that treats certain bacterial infections, such as some urinary, chest and eye infections. Because of recognised risks affecting tendons, nerves and the heart's rhythm, it is now reserved for situations where other antibiotics are unsuitable. It is taken as a tablet, or used as eye or ear drops, for the full course your prescriber recommends.
Education and reference only. This is a plain-language guide to Ofloxacin — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Ofloxacin is a fluoroquinolone antibiotic, one of a group of medicines that are highly effective but now used more cautiously in the UK. It is given as a tablet for some urinary, chest and other bacterial infections, and is also available as eye and ear drops for local infections. Following MHRA safety reviews, oral and injected fluoroquinolones are reserved for infections where first-choice antibiotics cannot be used, because of rare but serious and sometimes long-lasting side effects.
How it works
Ofloxacin blocks bacterial enzymes (DNA gyrase and topoisomerase IV) that bacteria need to copy and repair their DNA. Without these enzymes working, the bacteria cannot divide and are killed. It is active against a broad range of bacteria, which is why it has been used across several types of infection.
Company & origin
Originated / developed by: Daiichi Sankyo.
Developed in Japan and introduced in the 1980s, ofloxacin is a second-generation fluoroquinolone antibiotic.
Practical use
How to take Ofloxacin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take tablets with a glass of water, with or without food, spaced evenly through the day as directed.
- Separate doses by a few hours from milk and other dairy, antacids, and iron, zinc or calcium supplements.
- Keep well hydrated and avoid excessive sun or sunbeds, as your skin may burn more easily.
- Finish the full course even if you feel better, unless told to stop.
- Stop and seek prompt advice if you develop tendon pain, tingling or numbness, or low mood.
Weighing it up
Advantages & disadvantages of Ofloxacin
Advantages
- Broad-spectrum and effective against many bacteria, including some that resist other antibiotics.
- Well absorbed as a tablet, so it can sometimes avoid the need for a drip.
- Available as eye and ear drops for treating local infections directly.
Disadvantages
- Carries serious MHRA warnings, so it is reserved rather than first-choice for most infections.
- Can rarely cause lasting, disabling effects on tendons, nerves, muscles and mental health.
- Absorption is reduced by dairy, antacids and mineral supplements, so timing matters.
- May prolong the heart's QT interval, which is a concern alongside certain other medicines.
Practical use
Good to know
It is important to finish the whole course, even once you feel better, to clear the infection fully and reduce resistance. Tablets should be separated in time from dairy products, antacids, and supplements containing iron, zinc or calcium, which otherwise bind the antibiotic and stop it being absorbed. Stop and seek urgent advice if you notice tendon pain or swelling, new tingling or numbness, or low mood or confusion.
Who should not take it / use with caution
- People who have had a serious reaction to ofloxacin or another fluoroquinolone, or previous tendon problems with one.
- Generally avoided in pregnancy and breastfeeding, and in children and growing teenagers, unless there is no alternative.
- Used with great caution if you have epilepsy or a lowered seizure threshold, a known heart-rhythm (QT) problem, or myasthenia gravis, which it can worsen.
- Used with caution and usually avoided in people with, or at risk of, an aneurysm or tear of a major artery (the aorta) — for example existing aneurysm, certain connective-tissue conditions (such as Marfan or Ehlers-Danlos syndrome), or poorly controlled high blood pressure.
Monitoring
- Response of the infection and completion of the course
- For tendon, nerve, mood or heart-rhythm symptoms
- Kidney function may guide use in some people
Side effects
- Nausea, diarrhoea, stomach upset, headache or dizziness.
- Tendon pain or swelling (often the Achilles) that can rarely progress to rupture — stop and seek advice.
- Rarely, lasting nerve effects (tingling, numbness), mood or sleep changes, heart-rhythm changes, or a major artery problem (aortic aneurysm); these need urgent attention.
Key interactions
- Dairy, antacids and supplements containing iron, zinc, calcium or magnesium reduce absorption — separate the timing.
- Medicines that prolong the QT interval, and some that lower the seizure threshold, increase risk when combined.
- Care with warfarin (bleeding risk) and with theophylline; NSAIDs may add to the small seizure risk.
Available as: Tablets, plus eye drops and ear drops for local infections. A solution for infusion is used in hospital.
Answers
Ofloxacin: frequently asked questions
Why is ofloxacin not used as a first-choice antibiotic any more?
Following safety reviews, the MHRA advises that fluoroquinolones like ofloxacin are reserved for infections where other antibiotics cannot be used, because of rare but serious effects on tendons, nerves, muscles and mental health. Your prescriber weighs this carefully before choosing it.
Can I take it with milk or indigestion remedies?
Not at the same time. Dairy, antacids and supplements containing iron, zinc or calcium bind the antibiotic and stop it being absorbed, so separate them by a few hours. Plain water is fine.
What should make me stop taking ofloxacin straight away?
Stop and seek urgent advice if you get tendon pain or swelling, new tingling or numbness, severe headache, or sudden low mood or confusion. These warning signs should be acted on promptly.
Is ofloxacin the same as Tarivid?
Yes. Ofloxacin is the active-ingredient (generic) name and Tarivid is a brand name; they contain the same medicine.
Should I finish the whole course?
Yes, unless your prescriber tells you to stop. Completing the course helps clear the infection fully and reduces the chance of resistance, even though you may feel better partway through.
The wider class
About Fluoroquinolones
Ofloxacin belongs to the fluoroquinolones class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF: Ofloxacin.
- MHRA Drug Safety Update: Fluoroquinolone antibiotics.
- NICE CKS: Antibiotics.
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