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1. About ciprofloxacin

Ciprofloxacin is an antibiotic. It belongs to a group of antibiotics called fluoroquinolones.

It is used to treat serious infections, or infections when other anitbiotics have not worked.

It's used to treat bacterial infections, such as:

It can be used to help stop people getting meningitis if they have been really close to someone with the infection.

Ciprofloxacin is only available on prescription.

It comes as tablets, a liquid that you drink, eardrops, eyedrops and an eye ointment. It's also given by injection, but this is usually done in hospital.

Ciprofloxacin tablets and liquid are not used as often as some other types of antibiotics because there's a risk of serious side effects.

2. Key facts

  • Most adults and children can take ciprofloxacin.
  • The most common side effects of ciprofloxacin tablets and liquid are feeling sick (nausea) and diarrhoea.
  • Avoid taking the tablets or liquid together with dairy products like milk, cheese and yoghurt.
  • Ciprofloxacin is also known by the brand names Ciproxin (tablets and liquid), Ciloxan (eyedrops and eye ointment) and Cetraxal (eardrops).
  • Ciprofloxacin eardrops also come mixed with other medicines, such as dexamethasone (known as Cetraxal Plus) and fluocinolone (known as Cilodex).

3. Who can and can't take ciprofloxacin

Ciprofloxacin can be taken by most adults and children from the age of 1 year.

Ciprofloxacin is not suitable for some people.

To make sure ciprofloxacin is safe for you, tell your doctor if:

  • you have had an allergy to ciprofloxacin or any other medicine
  • you have had a serious side effect with ciprofloxacin or another antibiotic (particularly a fluroquinolone) in the past
  • you had diarrhoea when you have taken antibiotics before
  • you or someone in your family has an abdominal aortic aneurysm or any other problem with the aorta (the large blood vessel running from the heart to the abdomen)
  • you have fast, pounding or irregular heartbeats
  • you have problems with tendons
  • you have epilepsy or another health problem that puts you at risk of seizures
  • you have problems with your kidneys
  • you have diabetes, as ciprofloxacin might affect your blood sugars

4. How and when to take it

How you take your medicine depends on the type of ciprofloxacin and what you're taking it for. Follow the instructions that come with it.

Try to space the doses evenly throughout the day. Keep taking or using this medicine until the course is finished, unless your doctor tells you to stop.

How to take the tablets and liquid

Ciprofloxacin comes as 250mg, 500mg and 750mg tablets. It also comes as a liquid that contains 250mg in a 5ml spoonful (250mg/5ml).

The usual dose of ciprofloxacin is 250mg to 750mg twice a day. For some infections you might only need to take a single dose.

Doses are usually lower for children and people with kidney problems.

Swallow the tablets whole with lots of water. Do not chew them.

Ciprofloxacin liquid comes as granules that you need to dissolve in the special liquid provided. Follow the instructions that comes with your medicine.

Before taking ciprofloxacin liquid, shake the bottle for 15 seconds to make sure the granules have dissolved.

The liquid comes with a plastic syringe or spoon to help you take the right amount. If you do not have one, ask your pharmcist for one. Do not use a kitchen teaspoon as it will not give the right dose.

You can take ciprofloxacin tablets and liquid with or without food. however, avoid dairy produce like milk, cheese and yoghurt, as they can affect how your medicine works.

How to apply the eyedrops

You'll usually put 1 or 2 drops into the affected eye 4 times a day.

For severe infections, your doctor may tell you to use the drops as often as every 15 minutes for the first 6 hours. You can then reduce how often you use it.

  • Gently pull down your lower eyelid with a clean finger and tilt your head back.
  • Hold the bottle over your eye and allow a single drop to fall into the space between your lower lid and your eye.
  • Wipe away any extra liquid with a clean tissue.
  • Put in a second drop if you have been told to.

Do not touch your eye or eyelid with the dropper as it may cause infection to spread.

How to use the eye ointment

Put just over 1 centimetre of ointment on the affected eye 2 or 3 times a day, or as your doctor advises. If the infection is severe, your doctor may tell you to use it as often as every hour, and throughout the night.

  • Hold the tube with the nozzle close to your eye and gently squeeze the ointment into the space between your lower lid and your eye.

Do not touch your eye or eyelid with the nozzle as it may cause infection to spread.

How to use the eardrops

Put up to 5 drops into the affected ear twice a day, or as your doctor advises.

  • Warm the drops by holding the container in your hands for a few minutes.
  • Tilt your head and bring the container up to the affected ear, with the open end close to your ear hole.
  • Squeeze the drops into your ear.
  • If you can, lie down for at least 5 minutes afterwards.
  • If you are only treating 1 ear, turn your head to one side, so your affected ear is towards the ceiling.

What if I forget to take it?

If you forget a dose, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just skip the missed dose and take your next one as normal.

Make sure you finish your full course of antibiotics. Do not have a double dose to make up for a missed dose.


What if I take or use too much?

If you're using the eye ointment or the eye or eardrops, do not worry if you accidentally use a bit too much. This usually will not cause any problems.

Ciprofloxacin tablets or liquid

If you take more than your dose of the tablets or liquid, you may get side effects. These include feeling or being sick (nausea or vomiting), diarrhoea and a pounding or irregular hearbeat. If you have epilepsy, you might have seizures or fits.

Urgent advice: Speak to your doctor or pharmacist if:

  • your child takes too much ciprofloxacin
  • you take 2 extra doses of ciprofloxacin or more
  • you've taken too much ciprofloxacin and are getting side effects

5. Side effects

Like all medicines, ciprofloxacin can cause side effects although not everyone gets them.

Common side effects

Common side effects of ciprofloxacin happen in more than 1 in 100 people. Tell your doctor if these side effects bother you or do not go away:

  • feeling sick (nausea) after taking the tablets or liquid
  • diarrhoea after taking the tablets or liquid
  • red or uncomfortable eye with a stinging, burning or gritty feeling after using the eyedrops or ointment
  • bad taste in the mouth with the eyedrops or ointment
  • white specks on the surface of your eye after using the eyedrops or ointment

Serious side effects

Very few people taking or using ciprofloxacin have serious side effects.

They are less likely to happen with the eyedrops, eye ointment or eardrops.

These serious side effects can happen in less than 1 in 100 people. Stop taking ciprofloxacin and tell your doctor straight away if you have:

  • muscle weakness, pain or swelling in your joints or tendons. This often begins in the ankle or calf, but could also be in your shoulder, arms or legs. It can occur in the first 2 days of taking ciprofloxacin or even several months after stopping. It is more common in children
  • pain or abnormal sensations (such as pins and needles that do not go away, tingling, tickling, numbness or burning) or weakness in your body, especially in the legs or arms
  • severe tiredness, feel anxious or very low in mood, or have difficulty sleeping or remembering things
  • ringing in your ears (tinnitus), loss of taste, are seeing double, or have any other changes in your sight, smell, taste or hearing
  • diarrhoea (perhaps with muscle cramps) that contains blood or mucus – if you have severe diarrhoea without blood or mucus for more than 4 days, you should also speak to a doctor
  • a faster or irregular heartbeat
  • seizures or fits (this side effect can happen if you have epilepsy)


  • you have sudden, severe pain in your stomach, chest or back.

Do not drive yourself. Take the ciprofloxacin box or leaflet inside the packet plus any remaining medicine with you.

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to ciprofloxacin.


  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking


These are not all the side effects of ciprofloxacin.




6. How to cope with side effects

What to do about:

  • diarrhoea after taking the tablets or liquid – drink lots of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having dark strong-smelling pee. Do not take any other medicines to treat diarrhoea without speaking to a pharmacist or doctor
  • discomfort or redness in the eyes after using the drops or ointment – this should go away on its own. Do not drive or operate heavy machinery until your eyes feel comfortable again and your vision is clear
  • bad taste in your mouth after using the eyedrops or ointment – this should not last long after using your medicine. Drink some water or juice, or chew some sugar-free gum
  • white specks on the surface of your eye after using the eyedrops or ointment – keep taking your ciprofloxacin but tell your doctor if these side effects bother you or do not go away

7. Pregnancy and breastfeeding

Ciprofloxacin is not usually recommended in pregnancy or when breastfeeding.



For more information about how ciprofloxacin can affect you and your baby during pregnancy, read this leaflet on the Best Use of Medicines in Pregnancy (BUMPS) website.

Non-urgent advice: Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

8. Cautions with other medicines



  • antacids for heartburn or indigestion – take ciprofloxacin at least 2 hours after antacids. Do not take another antacid until at least 4 hours after your ciprofloxacin
  • methotrexate, a medicine used to treat conditions such as rheumatoid arthritis
  • phenytoin, a medicine for epilepsy
  • steroids, such as prednisolone
  • theophylline or aminophylline for asthma
  • tizanidine, a medicine used for muscle stiffness
  • warfarin, a blood thinner (anticoagulant)

Mixing ciprofloxacin with herbal remedies and supplements

Iron tablets (such as ferrous sulphate or ferrous fumarate), calcium and zinc supplements can affect ciprofloxacin. Leave 2 hours in between doses of these supplements and ciprofloxacin.




9. Common questions

How does it work?

Ciprofloxacin is from a group of medicines called fluoroquinolone (or quinolone) antibiotics.

Fluoroquinolone antibiotics work by killing the bacteria causing an infection.

How long does it take to work?


Tell your doctor if you do not start feeling better after taking or using ciprofloxacin for 2 to 3 days, or if you feel worse at any time.

Some infections will take longer to clear, such as bone infections like osteomyelitis. In this case, you should start to feel better after a week or maybe longer.

How long will I take it for?

It's very important that you keep taking ciprofloxacin until your course is finished. Do this even if you feel better. It will help to stop the infection coming back.

It is usual to take ciprofloxacin for a week or 2. For some infections you might only need to take it for a day, but up to 3 months for others.

Your doctor will tell you how long to take or use ciprofloxacin.

Is it safe to take for a long time?

Ciprofloxacin is generally used for a short time to clear an infection.

Many people take ciprofloxacin and have no side effects.

However, some people have serious side effects. These can happen during treatment or even months after stopping. In a few people, these can be long-lasting or never go away.

Because the side effects can be so serious, ciprofloxacin is not prescribed for more than 3 months at a time.

It's very important that you keep taking ciprofloxacin until your course is finished. Talk to your doctor or pharmacist if you are worried about this.

What will happen if I stop taking it?

Carry on taking ciprofloxacin until you've completed the course, even if you feel better.

If you stop your treatment early, the infection could come back. It also gives any remaining bacteria a chance to change or adapt so they are no longer affected by the antibiotic.

This is known as antibiotic resistance.

How is it different to other anitbiotics?

Ciprofloxacin is a fluoroquinolone (or quinolone) antibiotic.

Different antibiotics kill different types of bacteria.

Your doctor will choose an antibiotic depending on which types of bacteria they think are causing your infection.

Some antibiotics are more specific (narrow-spectrum) and some kill a wider range of bacteria (broad-spectrum).

Ciprofloxacin is a broad-spectrum antibiotic that was once used to treat a wide range of infections, especially respiratory and urinary tract infections.

Ciprofloxacin is not used as often as some other antibitotics because of the risk of serious side effects.

Other quinolone antibiotics include levofloxacin, moxifloxacin and ofloxacin.

All quinolones can be used to treat some chest, eye and genital infections.

Levofloxacin and ofloxacin are usually taken 1 or 2 times a day. Moxifloxacin is only taken once a day.

Levofloxacin also comes as a liquid that you breathe in for certain infections in your lungs.

Can I drink alcohol with it?

Yes, you can drink alcohol with ciprofloxacin.

Is there any food or drink I need to avoid?

Do not take the liquid or tablets with dairy products (such as milk, cheese and yoghurt) or drinks with added calcium (such as some dairy-free milks). They stop ciprofloxacin entering the body from the stomach.

Leave a gap of at least 2 hours between taking ciprofloxacin and having this type of food and drink. It's then OK to have some dairy or calcium as part of a balanced meal.

You do not need to avoid any food or drinks if you're using the eyedrops, eye ointment or eardrops.

Will it affect my fertility?

There's no firm evidence to suggest that taking ciprofloxacin will reduce fertility in either men or women.


Will it affect my contraception?

Ciprofloxacin does not affect any type of contraception, including the combined pill and emergency contraception.

But if ciprofloxacin makes you sick (vomit) or have severe diarrhoea for more than 24 hours, your contraceptive pills may not protect you from pregnancy.

Look on the pill packet to find out what to do.

Find out what to do if you're on the pill and you're being sick or have diarrhoea.

Can I drive or ride a bike?

Ciprofloxacin may make you feel tired or less alert.

Make sure you know how you react to ciprofloxacin before driving or riding a bike.

If you get stinging or burning in your eyes straight after applying ciprofloxacin eyedrops or eye ointment, do not drive or ride a bike. Wait until your eyes are comfortable again and your vision is clear.

Ear infections can make you lose your balance. If you're affected, it's best not to drive or ride a bike until you feel back to normal.

If in doubt talk to your doctor or pharmacist.

Page last reviewed: 12 September 2019
Next review due: 12 September 2022