Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Fluoroquinolone Antibacterial [EPC]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 199885
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Levofloxacin is a fluoroquinolone antibacterial indicated in adults (18 years of age and older) with infections caused by designated, susceptible bacteria and in pediatric patients where indicated (1, 12.4). • Pneumonia: Nosocomial (1.1) and Community Acquired (1.2, 1.3) • Skin and Skin Structure Infections (SSSI): Complicated (1.4) and Uncomplicated (1.5) • Chronic bacterial prostatitis (1.6) • Inhalational Anthrax, Post-Exposure in adult and pediatric patients (1.7) • Plague in adult and pediatric patients (1.8) • Urinary Tract Infections (UTI): Complicated (1.9, 1.10) and Uncomplicated (1.12) • Acute Pyelonephritis (1.11) • Acute Bacterial Exacerbation of Chronic Bronchitis (1.13) • Acute Bacterial Sinusitis (1.14) Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of levofloxacin and other antibacterial drugs, levofloxacin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria (1.15). 1.1 Nosocomial Pneumonia Levofloxacin tablets are indicated in adult patients for the treatment of nosocomial pneumonia due to methicillin-susceptible Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Escherichia coli, Klebsiella pneumoniae, Haemophilus influenzae, or Streptococcus pneumoniae. Adjunctive therapy should be used as clinically indicated. Where Pseudomonas aeruginosa is a documented or presumptive pathogen, combination therapy with an anti-pseudomonal β-lactam is recommended [see Clinical Studies ( 14.1) ]. 1.2 Community-Acquired Pneumonia: 7 to 14 day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of community-acquired pneumonia due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae (including multi-drug-resistant Streptococcus pneumoniae [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydophila pneumoniae, Legionella pneumophila, or Mycoplasma pneumoniae [see Dosage and Administration (2.1) and Clinical Studies ( 14.2)]. […]
About this medicine
Levofloxacin tablets, USP are synthetic antibacterial agents for oral administration. Chemically, levofloxacin, a chiral fluorinated carboxyquinolone, is the pure (-)-(S)-enantiomer of the racemic drug substance ofloxacin. The chemical name is (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido [1,2,3-de]-1,4-benzoxazine-6-carboxylic acid hemihydrate. Figure 1: The Chemical Structure of Levofloxacin, USP The molecular formula is C18H20FN3O4 • 1⁄2 H2O and the molecular weight is 370.38. Levofloxacin, USP is a light yellowish-white to yellow-white crystals or crystalline powder. The molecule exists as a zwitterion at the pH conditions in the small intestine. The data demonstrate that from pH 0.6 to 5.8, the solubility of levofloxacin, USP is essentially constant (approximately 100 mg/mL). Levofloxacin, USP is considered soluble to freely soluble in this pH range, as defined by USP nomenclature. Above pH 5.8, the solubility increases rapidly to its maximum at pH 6.7 (272 mg/mL) and is considered freely soluble in this range. Above pH 6.7, the solubility decreases and reaches a minimum value (about 50 mg/mL) at a pH of approximately 6.9. Levofloxacin, USP has the potential to form stable coordination compounds with many metal ions. This in vitro chelation potential has the following formation order: Al+3>Cu+2>Zn+2>Mg+2>Ca+2. Levofloxacin Tablets, USP are available as film-coated tablets and contain the following inactive ingredients: • 250 mg: croscarmellose sodium, hypromellose, iron oxide red, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. • 500 mg: croscarmellose sodium, hypromellose, iron oxide red, iron oxide yellow magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. • 750 mg: croscarmellose sodium, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. Levofloxacin tablets, USP meets USP Dissolution Test 2. levofloxacinfigure1
How it works
12.1 Mechanism of Action Levofloxacin is a member of the fluoroquinolone class of antibacterial agents [see Microbiology ( 12.4)].
Who should not take it
Levofloxacin tablets are contraindicated in persons with known hypersensitivity to levofloxacin, or other quinolone antibacterials [see Warnings and Precautions ( 5.3 )]. Known hypersensitivity to levofloxacin or other quinolones ( 4 , 5.7 )
Warnings and cautions
Anaphylactic reactions and allergic skin reactions, serious, occasionally fatal, may occur after first dose ( 4 , 5.7 ) Hematologic (including agranulocytosis, thrombocytopenia), and renal toxicities may occur after multiple doses ( 5.6 ) Hepatotoxicity: Severe, and sometimes fatal, hepatoxicity has been reported. Discontinue immediately if signs and symptoms of hepatitis occur ( 5.8 ) Clostridium difficile -associated colitis: evaluate if diarrhea occurs ( 5.10 ) Prolongation of the QT interval and isolated cases of torsade de pointes have been reported. Avoid use in patients with known prolongation, those with hypokalemia, and with other drugs that prolong the QT interval ( 5.11 , 8.5 ) 5.1 Disabling and Potentially Irreversible Serious Adverse Reactions Including Tendinitis and Tendon Rupture, Peripheral Neuropathy, and Central Nervous System Effects Fluoroquinolones, including levofloxacin, have been associated with disabling and potentially irreversible serious adverse reactions from different body systems that can occur together in the same patient. Commonly seen adverse reactions include tendinitis, tendon rupture, arthralgia, myalgia, peripheral neuropathy, and central nervous system effects (hallucinations, anxiety, depression, insomnia, severe headaches, and confusion). These reactions can occur within hours to weeks after starting levofloxacin. Patients of any age or without pre-existing risk factors have experienced these adverse reactions [see Warnings and Precautions (5.2 , 5.3 , 5.4 )]. Discontinue levofloxacin immediately at the first signs or symptoms of any serious adverse reaction. In addition, avoid the use of fluoroquinolones, including levofloxacin, in patients who have experienced any of these serious adverse reactions associated with fluoroquinolones. 5.2 Tendinopathy and Tendon Rupture Fluoroquinolones, including levofloxacin, have been associated with an increased risk of tendinitis and tendon rupture in all ages [see Warnings and Precautions ( 5.1) and Adverse Reactions ( 6.2)]. […]
Reported side effects
The most common reactions (≥3%) were nausea, headache, diarrhea, insomnia, constipation and dizziness ( 6.2 ). To report SUSPECTED ADVERSE REACTIONS, contact Hetero Labs Limited at 1-866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Serious and Otherwise Important Adverse Reactions The following serious and otherwise important adverse drug reactions are discussed in greater detail in other sections of labeling: • Disabling and Potentially Irreversible Serious Adverse Reactions [ see Warnings and Precautions (5.1)] • Tendinitis and Tendon Rupture [see Warnings and Precautions ( 5.2)] • Peripheral Neuropathy [see Warnings and Precautions (5.3)] • Central Nervous System Effects [see Warnings and Precautions ( 5.4)] • Exacerbation of Myasthenia Gravis [see Warnings and Precautions ( 5.5)] • Other Serious and Sometimes Fatal Reactions [see Warnings and Precautions ( 5.6)] • Hypersensitivity Reactions [see Warnings and Precautions (5.7)] • Hepatotoxicity [see Warnings and Precautions ( 5.8)] • Risk of Aortic Aneurysm and Dissection [see Warnings and Precautions ( 5.9 )] • Clostridium difficile-Associated Diarrhea [see Warnings and Precautions ( 5.10 )] • Prolongation of the QT Interval [see Warnings and Precautions ( 5.11 )] • Musculoskeletal Disorders in Pediatric Patients [see Warnings and Precautions ( 5.12 )] • Blood Glucose Disturbances [see Warnings and Precautions ( 5.13 )] • Photosensitivity/Phototoxicity [see Warnings and Precautions ( 5.14 )] • Development of Drug Resistant Bacteria [see Warnings and Precautions ( 5.15 )] Crystalluria and cylindruria have been reported with quinolones, including levofloxacin. Therefore, adequate hydration of patients receiving levofloxacin should be maintained to prevent the formation of a highly concentrated urine [see Dosage and Administration ( 2.5 )]. 6.2 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. […]
Interactions with other medicines
Interacting Drug Interaction Multivalent cation-containing products including antacids, metal cations or didanosine Absorption of levofloxacin is decreased when the tablets are taken within 2 hours of these products. (2.4, 7.1) Warfarin Effect may be enhanced. Monitor prothrombin time, INR and watch for bleeding (7.2) Antidiabetic agents Carefully monitor blood glucose (5.13, 7.3) 7.1 Chelation Agents: Antacids, Sucralfate, Metal Cations, Multivitamins While the chelation by divalent cations is less marked than with other fluoroquinolones, concurrent administration of levofloxacin tablets with antacids containing magnesium, or aluminum, as well as sucralfate, metal cations such as iron, and multivitamin preparations with zinc may interfere with the gastrointestinal absorption of levofloxacin, resulting in systemic levels considerably lower than desired. Tablets with antacids containing magnesium, aluminum, as well as sucralfate, metal cations such as iron, and multivitamin preparations with zinc or didanosine may substantially interfere with the gastrointestinal absorption of levofloxacin, resulting in systemic levels considerably lower than desired. These agents should be taken at least two hours before or two hours after oral levofloxacin administration. 7.2 Warfarin No significant effect of levofloxacin on the peak plasma concentrations, AUC, and other disposition parameters for R- and S- warfarin was detected in a clinical study involving healthy volunteers. Similarly, no apparent effect of warfarin on levofloxacin absorption and disposition was observed. However, there have been reports during the postmarketing experience in patients that levofloxacin enhances the effects of warfarin. Elevations of the prothrombin time in the setting of concurrent warfarin and levofloxacin use have been associated with episodes of bleeding. Prothrombin time, International Normalized Ratio (INR), or other suitable anticoagulation tests should be closely monitored if levofloxacin is administered concomitantly with warfarin. Patients should also be monitored for evidence of bleeding [see Adverse Reactions ( 6.3) and Patient Counseling Information ( 17)]. […]
Use in specific groups
• Geriatrics: Severe hepatotoxicity has been reported. The majority of reports describe patients 65 years of age or older (5.8, 8.5, 17). May have increased risk of tendinopathy (including rupture), especially with concomitant corticosteroid use (5.2, 8.5, 17). May be more susceptible to prolongation of the QT interval. (5.11, 8.5, 17). • Pediatrics: Musculoskeletal disorders (arthralgia, arthritis, tendinopathy, and gait abnormality) seen in more levofloxacin-treated patients than in comparator. Shown to cause arthropathy and osteochondrosis in juvenile animals (5.12, 8.4, 13.2). Safety in pediatric patients treated for more than 14 days has not been studied. Risk-benefit appropriate only for the treatment of inhalational anthrax (post-exposure) (1.7, 2.2, 8.4, 14.9) and plague (1.8, 2.2, 8.4, 14.10) 8.1 Pregnancy Pregnancy Category C. Levofloxacin was not teratogenic in rats at doses as high as 810 mg/kg/day which corresponds to 9.4 times the highest recommended oral human dose based upon relative body surface area. The oral dose of 810 mg/kg/day to rats caused decreased fetal body weight and increased fetal mortality. No teratogenicity was observed when rabbits were dosed orally as high as 50 mg/kg/day which corresponds to 1.1 times the highest recommended oral human dose based upon relative body surface area. There are, however, no adequate and well-controlled studies in pregnant women. Levofloxacin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. 8.3 Nursing Mothers Based on data on other fluoroquinolones and very limited data on levofloxacin, it can be presumed that levofloxacin will be excreted in human milk. Because of the potential for serious adverse reactions from levofloxacin in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. 8.4 Pediatric Use Quinolones, including levofloxacin, cause arthropathy and osteochondrosis in juvenile animals of several species. [see Warnings and Precautions ( 5.12 ) and Animal Toxicology and/or Pharmacology ( 13.2 )]. […]
If too much is taken
In the event of an acute overdosage, the stomach should be emptied. The patient should be observed and appropriate hydration maintained. Levofloxacin is not efficiently removed by hemodialysis or peritoneal dialysis. Levofloxacin exhibits a low potential for acute toxicity. Mice, rats, dogs and monkeys exhibited the following clinical signs after receiving a single high dose of levofloxacin: ataxia, ptosis, decreased locomotor activity, dyspnea, prostration, tremors, and convulsions. Doses in excess of 1500 mg/kg orally and 250 mg/kg IV produced significant mortality in rodents.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 4 March 2025. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.