Levofloxacin: Uses, side effects & contraindications!

Levofloxacin is a quinolone antibacterial of the class fluoroquinolone. It is a part of the second generation of quinolone antibiotics.

Levofloxacin is similar to ciprofloxacin in the terms of action, uses, bacterial spectrum & side effects.


  • Treatment of lung infection
  • Nosocomial pneumonia
  • Sinus infection (sinusitis)
  • Skin infections
  • Ear infection
  • Bone & joint infection
  • UTI
  • Infection of the prostate (prostatitis) by bacteria that may be resistant to other antibiotics.
  • Infectious diarrhea by E.coli & campylobacter
  • Treatment of obstetric infections (related to female reproductive system)
  • Mastitis (infection of the breast)
  • Acute pyelonephritis
  • Inhalational anthrax
  • Treatment of bacterial plague.


Types of dosage forms

  • Tablets: 250, 500 and 750 mg
  • Oral solution: 25 mg/mL
  • Injection: 500 mg/20 ml and 750 mg/30 ml
  • Premix ready to use injection: 250 mg/50 ml, 500 mg/100 ml, and 750 mg/150 ml

Dosage guide

  • 250-750 mg tablet given once daily for 3-14 days depending on the type of infection.
  • 500 mg/day for 60 days in Anthrax

Missed dose: If a dose is missed & it is way past the time to take the particular dose, skip the dose & do not take it close to or along with the following dose.

a) Treatment is followed by removal of drug by inducing vomiting or administering a gastric lavage.
b) Maintaining appropriate hydration & nutrition.


  • Nausea
  • Vomiting
  • Change in taste
  • Diarrhea or constipation
  • Headache
  • Hives/rash
  • Difficulty sleeping
  • Abdominal pain
  • Flatulence
  • Allergic reaction


  • Death of peripheral nerve cells
  • Low blood sugar
  • Severe diarrhea
  • Abnormal heart beat
  • Imbalance in liver function
  • Sensitivity to sunrays
  • CNS issues like seizures, delusion, hallucinations, etc.
  • Inflammation of the colon
  • Dysapnea
  • Syncope/fainting
  • Low blood pressure
  • Shock
  • Kidney failure


Levofloxacin is contraindicated in patients & precaution is advised, with following conditions or disorders:

  • Muscle or nerve disorder like myasthenia gravis
  • Kidney disease
  • Head injury
  • Brain tumor
  • People with CNS diseases or disorders when given levofloxacin can develop rare & severe convulsions.
  • QT prolongation
  • Autoimmune disorders
  • Genetic/Hereditary disorders
  • Low levels of serum/blood potassium
  • Diabetes
  • Problems in blood flow
  • Aneurysm/blood clots
  • Hypertension
  • Bone or tendon problems.


Drugs whose blood level is increased/or effectiveness is increased (unwanted) when given in presence of levofloxacin:

  • Theophylline given in asthma
  • Tizanidine given in muscle spasticity
  • Warfarin – blood thinning drug
  • Glyburide – leads to very low blood sugar
  • Sulfonylureas – leads to very low blood sugar
  • Sildenafil
  • Sucralfate
  • Diuretics

Drugs that reduce the effectiveness of levofloxacin when given in combination:

  • Iron salts
  • Antacids
  • Calcium containing salts, these drugs can bind with levofloxacin and reduce its absorption.
  • Sevelamer
  • Levofloxacin when taking along with NSAIDs can increase CNS stimulation and cause varying symptoms.

Drug-Food interaction

  • Milk and other dairy products reduce the effectiveness of the drug.
  • Orange juice reduces the effectiveness of the drug.
  • When oral solution is given with enteric tube feedings, the action of the drug is reduced.
  • Caffeine concentration increases when given in addition with the drug.
  • Multivitamins can interfere with the absorption of the drug.
  • Alcohol not to be taken along with the drug.


  • Pregnancy: Levofloxacin is categorized as a category C drug, which includes drugs that have no adequate information or controlled studies on it. Although harm to fetus is speculated.
  • Breastfeeding: Fluoroquinolones are present in the breast milk of the mother, and therefore can pass on to infants causing serious adverse effects, although less concentration of levofloxacin is present in the breast milk, & therefore can be prescribed when properly monitored.
  • Children: Levofloxacin is not recommended in children except in life threatening infections. For eg: Oral & IV drug are approved for children in two indications: Anthrax & complicated UTI.