Ciproxin (Ciprofloxacin)

How does it work?

Ciproxin tablets, suspension and infusion all contain the active ingredient ciprofloxacin, which is a type of medicine called a quinolone antibiotic. Antibiotics are used to treat infections caused by bacteria. (NB. Ciprofloxacin is also available without a brand name, ie as the generic medicine.)

Ciprofloxacin works by killing the bacteria that are causing an infection. It does this by entering the bacterial cells and inhibiting a bacterial enzyme called DNA-gyrase. This enzyme is involved in replicating and repairing the genetic material (DNA) of the bacteria. If this enzyme doesn't work, the bacteria cannot reproduce or repair themselves and this kills the bacteria.

Ciprofloxacin is effective against a large number of bacteria, some of which tend to be resistant to other commonly used antibiotics. It is particularly useful against a sub-group of bacteria called Gram-negative bacteria, including salmonella, shigella, campylobacter, neisseria, and pseudomonas. It is used to treat a wide range of infections, including infections of the chest, urinary tract and of the gastrointestinal system. It is also used as a single dose treatment for gonorrhoea.

To make sure the bacteria causing an infection are susceptible to ciprofloxacin your doctor may take a tissue sample, for example a swab from the throat or skin, or a urine or blood sample.

What is it used for?

In adults, ciprofloxacin can be used to treat the infections below, when caused by susceptible bacteria.

  • Bacterial infections of the lungs and airways (respiratory tract), such as pneumonia (but not 1st line treatment of pneumococcal pneumonia), acute bronchitis, bronchiectasis and lung infections in cystic fibrosis or chronic bronchitis.
  • Bacterial ear, nose and throat infections such as sinusitis, otitis media and otitis externa.
  • Bacterial eye infections such as bacterial conjunctivitis.
  • Bacterial infections of the urinary tract, such as cystitis, kidney infections (pyelonephritis), urethritis.
  • Bacterial infection of the prostate gland (prostatitis) or testicles (epididymitis).
  • Bacterial infections of the skin and soft tissue, such as infected ulcers, wounds or burns, abscesses, cellulitis, erysipelas.
  • Bacterial infections of bones and joints, such as osteomyelitis and septic arthritis.
  • Abdominal bacterial infections, such as peritonitis or abdominal abscesses.
  • Bacterial infections of the stomach and intestines, such as typhoid fever or infective diarrhoea.
  • Bacterial infections of the biliary tract or gall bladder.
  • Bacterial infections in the pelvis, such as pelvic inflammatory disease or infections in the uterus (endometritis) or uterine tube (salpingitis).
  • Gonorrhoea.
  • Bacterial infection of the blood (septicaemia or blood poisoning).
  • Preventing infections in people having stomach or intestinal surgery or endoscopic procedures, where there is an increased risk of infection.
  • Preventing or treating anthrax affecting the lungs, following exposure to anthrax spores.

In children, ciprofloxacin can be used to treat the infections below, when caused by susceptible bacteria.

  • 2nd and 3rd line treatment of complicated urinary tract infections and kidney infections (pyelonephritis) in children and adolescents aged 1 to 17 years.
  • Lung infections caused by a type of bacteria called Pseudomonas aeruginosa in children and adolescents aged 5 to 17 years with cystic fibrosis.
  • Preventing or treating anthrax affecting the lungs, following exposure to anthrax spores.

How do I take it?

  • The dose of this medicine and how long it needs to be taken for depends on your kidney function and the type of infection you have. Follow the instructions given by your doctor. These will be printed on the dispensing label that your pharmacist has put on the packet of medicine.
  • Ciprofloxacin is usually taken twice a day (every 12 hours).
  • Ciprofloxacin tablets should be swallowed whole and not chewed.
  • Bottles of suspension should be shaken before measuring out a dose. Only use the measuring spoon provided with the suspension. You should not use a regular teaspoon or tablespoon to take the medicine, as this will not give an accurate dose.
  • Ciprofloxacin can be taken either with or without food.
  • You should not take milk, yoghurt, antacids for indigestion or heartburn, or medicines containing calcium, iron, zinc, magnesium or aluminium at the same time as ciprofloxacin. This is because these can reduce the absorption of the antibiotic from the gut. (See end of factsheet for more information.)
  • Unless your doctor tells you otherwise, it is important that you finish the prescribed course of this antibiotic medicine, even if you feel better or it seems the infection has cleared up. Stopping the course early increases the chance that the infection will come back and that the bacteria will grow resistant to the antibiotic.


  • This medicine may reduce your ability to drive or operate machinery safely. This effect may be enhanced by drinking alcohol. Do not drive or operate machinery until you know how this medicine affects you and you are sure it won't affect your performance.
  • You should make sure you drink plenty of fluid while taking this medicine. This is to reduce the risk of crystals of the medicine forming in the urine.
  • Avoid exposing your skin to excessive sunlight, sunlamps or sunbeds while taking ciprofloxacin, as it may increase the sensitivity of your skin to UV light. If you get a rash or other skin reaction on exposure to sunlight you should stop taking this medicine and consult your doctor.
  • Treatment with antibiotics can sometimes cause overgrowth of other organisms that are not susceptible to the antibiotic, for example fungi or yeasts such as Candida. This may sometimes cause infections such as thrush. Tell your doctor if you think you have developed a new infection during or after taking this antibiotic.
  • Broad-spectrum antibiotics can sometimes cause inflammation of the bowel (colitis). For this reason, if you get diarrhoea either during or after taking this medicine, particularly if it becomes severe or persistent, or contains blood or mucus, you should consult your doctor immediately.
  • Quinolone antibiotics may rarely cause tendon inflammation (tendinitis) and tendon rupture. People aged over 60, people who have had a kidney, heart, or lung transplant and those taking corticosteroid medication are most at risk of this. You should stop taking this medicine immediately if you experience any pain or inflammation in your joints during treatment. Rest the affected limb(s) and consult a doctor immediately.

Use with caution in

  • Children and adolescents.
  • People over 60 years of age.
  • People using corticosteroid medicines.
  • People who have had a kidney, heart, or lung transplant.
  • Decreased kidney function.
  • History of convulsions (fits), eg epilepsy.
  • People with conditions that increase the risk of seizures.
  • Abnormal muscle weakness (myasthenia gravis).
  • History of psychiatric illness.
  • People who a lack an enzyme called G6PD in their blood, or who have a family history of this disorder (G6PD deficiency).
  • Heart disease.
  • People with a personal or family history of an abnormal heart rhythm seen on a heart monitoring trace (ECG) as a 'prolonged QT interval'.

Not to be used in

  • History of tendon disorders caused by previous treatment with a quinolone-type antibiotic.
  • Allergy to other quinolone-type antibiotics, eg norfloxacin, ofloxacin.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • This medicine is not recommended for use in pregnancy. This is because ciprofloxacin has been shown to cause joint disease in immature animals and may therefore have this effect in humans. There are usually safer alternative antibiotics available. Seek medical advice from your doctor.
  • Ciprofloxacin passes into breast milk. It is not recommended for use during breastfeeding, as there are usually safer alternative antibiotics available. Seek medical advice from your doctor.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.

Common (affect between 1 in 10 and 1 in 100 people)

  • Nausea.
  • Diarrhoea.

Uncommon (affect between 1 in 100 and 1 in 1000 people)

  • Rash.
  • Itching.
  • Loss of appetite.
  • Headache.
  • Dizziness.
  • Feeling weak or tired (asthenia).
  • Sleep disturbances.
  • Hyperactivity or agitation.
  • Taste disturbances.
  • Abdominal pain, flatulence (wind) or indigestion.
  • Vomiting.
  • Joint or back pain.
  • Fungal infections.

Rare (affect between 1 in 1000 and 1 in 10,000 people)

  • Disturbances in the numbers of blood cells in the blood.
  • Increased blood sugar levels (hyperglycaemia).
  • Confusion.
  • Anxiety.
  • Depression. Tell your doctor straight away if you notice any change in your mood, feelings or thoughts while taking this medicine.
  • Hallucinations.
  • Abnormal dreams.
  • Tremor.
  • Convulsions.
  • Pins and needles, burning or numb sensations. Tell your doctor straight away if you notice any strange sensations while taking this medicine.
  • Visual disturbances.
  • Hearing problems, including tinnitus.
  • Increased heart rate.
  • Low blood pressure or fainting.
  • Sweating.
  • Shortness of breath.
  • Muscle pain or cramps.
  • Increased sensitivity of the skin to sunlight (photosensitivity - see warning section above).
  • Inflammation of the bowel lining (colitis - see warning section above).
  • Liver or kidney disorders. Tell your doctor if you experience any of the following symptoms while taking this medicine, as they may suggest a problem with your liver: rapidly feeling weak or unwell, unexplained itching, loss of appetite, abdominal pain, yellowing of the skin or whites of the eyes (jaundice) or unusually dark urine.

Very rare (affect less than 1 in 10,000 people)

  • Disturbances in smell.
  • Tendon disorders (see warning section above).
  • Psychotic reactions.
  • Migraine.
  • Inflammation of the pancreas (pancreatitis).
  • Severe allergic skin reactions. Consult your doctor immediately if you get a severe rash, skin peeling, or painful blisters in the mouth/nose or genitals while taking this medicine.

The side effects listed above may not include all of the side effects reported by the medicine's manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.

You should not take any of the following medicines at the same time of day as your ciprofloxacin dose, as they can reduce the absorption of the ciprofloxacin from the gut and make it less effective. If you need to take any of these, the doses should be separated from your ciprofloxacin dose by at least four hours:

  • antacids for indigestion or heartburn
  • iron, calcium, magnesium or zinc supplements
  • other medicines containing calcium, magnesium, aluminium, zinc or iron
  • sevelamer
  • sucralfate
  • Videx chewable/dispersible tablets (these contain an antacid).

Strontium ranelate may also reduce the absorption of ciprofloxacin from the gut and could make it less effective. If you are taking strontium for osteoporosis its manufacturer recommends that you stop taking it temporarily while you are taking a course of ciprofloxacin.

If ciprofloxacin is used in combination with any of the following medicines there may be an increased risk of seizures (fits):

  • theophylline (ciprofloxacin also increases the level of theophylline in the blood - see below)
  • non-steroidal anti-inflammatory drugs (NSAIDs) such as indometacin, fenbufen, naproxen.

Ciprofloxacin can affect the blood level of phenytoin. As it can also increase the risk of seizures, it should generally be avoided in people with epilepsy.

Ciprofloxacin may enhance the anti-blood-clotting effect of anticoagulant medicines such as warfarin. As this may increase the risk of bleeding, your blood clotting time (INR) should be monitored more frequently if you are taking ciprofloxacin with an anticoagulant.

If ciprofloxacin is taken with the following medicines it may increase their blood levels, with the following effects:

  • ciclosporin (increased risk of side effects on the kidneys)
  • clozapine (possible increased risk of side effects)
  • duloxetine (ciprofloxacin should not be taken by people taking duloxetine).
  • glibenclamide (may rarely cause an excessive drop in blood sugar)
  • methotrexate (may increase the risk of toxicity - people taking this combination should be monitored)
  • ropinirole (possible increased risk of side effects)
  • theophylline (ciprofloxacin should not be used in combination with theophylline unless the dose of theophylline is reduced and the theophylline level can be monitored with blood tests)
  • tizanidine (increased risk of significant side effects - ciprofloxacin should not be taken by people taking tizanidine)
  • zolmitriptan (increased risk of side effects - lower dose of zolmitriptan recommended).

Probenecid may increase the amount of ciprofloxacin in the blood.

Oral typhoid vaccine (Vivotif) should not be taken until at least three days after you have finished a course of this antibiotic, because the antibiotic could make the vaccine less effective.

In the past, women using hormonal contraception such as the pill or patch would be advised to use an extra method of contraception (eg condoms) while having treatment with an antibiotic like this one and for seven days after finishing the course. However, this advice has now changed. You no longer need to use an extra method of contraception with the pill, patch or vaginal ring while you have a course of antibiotics. This change in advice comes because to date there is no evidence to prove that antibiotics (other than rifampicin or rifabutin) affect these contraceptives. This is the latest guidance from the Faculty of Sexual & Reproductive Healthcare.

However, if you are taking the contraceptive pill and experience vomiting or diarrhoea as a result of treatment with this antibiotic, you should follow the instructions for vomiting and diarrhoea described in the leaflet provided with your pills.

Other medicines containing the same active ingredient

Ciloxan eye drops and eye ointment

Ciprofloxacin tablets and infusion are also available without a brand name, ie as the generic medicine.