Levofloxacin (Tavanic)

How does it work?

Tavanic tablets and injection contain the active ingredient levofloxacin, which is a type of medicine called a quinolone antibiotic. Antibiotics are used to treat infections caused by bacteria. (NB Levofloxacin is also available without a brand name, ie as the generic medicine.)

Levofloxacin 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.

Levofloxacin is effective against a large number of bacteria. It is used to treat a range of infections, including infections of the chest, urinary tract and skin.

To make sure the bacteria causing an infection are susceptible to levofloxacin, 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?

  • Bacterial infection of the sinuses (sinusitis).
  • Acute flare-ups of chronic bronchitis.
  • Community-acquired pneumonia.
  • Bacterial infections of the urinary tract, such as cystitis and kidney infections (pyelonephritis).
  • Chronic bacterial infection of the prostate gland (prostatitis).
  • Bacterial infections of the skin or soft tissue.

How do I take it?

  • The dose of this medicine, how often it needs to be taken and how long it needs to be taken for depends on the type and severity of infection you have and your kidney function. 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.
  • Tavanic tablets are usually taken once or twice a day. The tablets should be swallowed without chewing or crushing, however the tablets are scored and can be broken. They can be taken either with or without food. Try to take them at regular intervals.
  • You should not take iron tablets or indigestion remedies at the same time of day as this medicine, because these can reduce the absorption of the antibiotic from the gut. If you need to take iron tablets or indigestion remedies they should be taken at least two hours before or after taking this medicine.
  • 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 cause dizziness, drowsiness or visual disturbances that may reduce your ability to drive or operate machinery safely. Do not drive or operate machinery until you know how this medicine affects you and you are sure it won't affect your performance.
  • Avoid exposing your skin to excessive sunlight, sunlamps or sunbeds while taking levofloxacin, 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, 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

  • People over 60 years of age.
  • People using corticosteroid medicines.
  • People who have had a kidney, heart, or lung transplant.
  • Decreased kidney function.
  • People with a history or risk of seizures (fits).
  • History of psychiatric illness.
  • Abnormal muscle weakness (myasthenia gravis).
  • Diabetes.
  • People who lack an enzyme called G6PD in their blood (G6PD deficiency).
  • Hereditary blood disorders called porphyrias.
  • 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'.
  • People with a very slow heart rate (bradycardia).
  • People with disturbances in the levels of salts in their blood, in particular low levels of potassium or magnesium (hypokalaemia or hypomagnesaemia).

Not to be used in

  • Children and growing adolescents.
  • Allergy to other quinolone-type antibiotics, eg norfloxacin, ciprofloxacin.
  • History of tendon disorders caused by previous treatment with a quinolone-type antibiotic.
  • Epilepsy.
  • Pregnancy.
  • Breastfeeding.

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 should not be used in pregnancy. This is because levofloxacin 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.
  • It is not known if this medicine passes into breast milk. It should not be used 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)

  • Feeling sick.
  • Diarrhoea.
  • Alteration in results of liver function tests.

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

  • Gut disturbances such as vomiting, abdominal pain, indigestion, wind, constipation.
  • Loss of appetite.
  • Overgrowth of fungi, which may cause infections such as thrush.
  • Difficulty sleeping (insomnia).
  • Nervousness.
  • Dizziness.
  • Headache.
  • Sleepiness.
  • Feeling weak (asthenia).
  • Rash or itching.

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

  • Decreased numbers of white blood cells or platelets in the blood.
  • Tingling or pins and needles sensations (consult your doctor immediately if you experience this).
  • Tremor.
  • Convulsions.
  • Confusion.
  • Anxiety, agitation.
  • Depression or psychotic reactions (consult your doctor immediately if you experience any distressing feelings, thoughts about harming yourself, mood changes or other unusual change in behaviour while taking this medicine).
  • Increased heart rate.
  • Low blood pressure.
  • Shortness of breath or difficulty breathing.
  • Tendon disorders (see warning section above).
  • Pain in the muscles or joints.

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

  • Low blood sugar (hypoglycaemia), particularly in people with diabetes.
  • Disturbances in hearing or vision.
  • Disturbance in sense of taste or smell.
  • Liver or kidney disorders. If you experience any yellowing of your skin or eyes (jaundice), unusually dark urine, itching, loss of appetite or abdominal pain during treatment you should stop taking this medicine and consult your doctor immediately, as these symptoms may suggest a problem with your liver.
  • Inflammation of the bowel lining (colitis). See warning section above.
  • Abnormal reaction of the skin the light (photosensitivity - see warning section above).
  • Severe 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 levofloxacin dose, as they can reduce the absorption of the levofloxacin from the gut and make it less effective. If you need to take any of these, their doses should be separated from your levofloxacin dose by at least two hours:

  • antacids (for indigestion) containing aluminium or magnesium
  • iron preparations
  • sucralfate (this is best taken at least two hours AFTER the levofloxacin).

Strontium ranelate may also reduce the absorption of levofloxacin 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 levofloxacin.

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

  • theophylline
  • non-steriodal anti-inflammatory drugs (NSAIDs) such as indometacin, fenbufen, naproxen.

Levofloxacin may enhance the anti-blood-clotting effect of anticoagulants 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 levofloxacin in combination with an anticoagulant.

Levofloxacin may increase the blood level of the immunosuppressants ciclosporin and tacrolimus. This could increase the risk of side effects on the kidneys from these medicines.

There may be an increased risk of abnormal heart rhythms ('prolonged QT interval' on a heart monitoring trace or ECG) if this medicine is taken with other medicines that can increase the risk of this, for example those listed below:

  • atomoxetine
  • medicines to treat abnormal heart rhythms (antiarrhythmics), eg amiodarone, procainamide, quinidine, disopyramide, sotalol
  • the antihistamines astemizole, terfenadine or mizolastine
  • certain antidepressants, eg maprotiline, amitriptyline, imipramine
  • certain antipsychotics, eg thioridazine, chlorpromazine, sertindole, haloperidol, pimozide
  • certain antimalarials, eg halofantrine, chloroquine, quinine, Riamet, mefloquine
  • certain other antimicrobials, eg erythromycin, clarithromycin, voriconazole or pentamidine
  • cisapride.

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

Levofloxacin tablets are also available without a brand name, ie as the generic medicine.