Last reviewed 2026-04-20 · How we verify

Avelox (moxifloxacin)

Fourth-generation fluoroquinolone with the broadest spectrum, covering gram-positive, gram-negative, anaerobic, and atypical organisms.

Moxifloxacin (Avelox) is a fourth-generation fluoroquinolone developed by Bayer, approved in 1999. Broadest spectrum fluoroquinolone including anaerobic coverage. Key component of MDR-TB regimens. Available generically.

At a glance

Mechanism of action

Moxifloxacin has the broadest antimicrobial spectrum of any fluoroquinolone, including anaerobic coverage. It is a key drug in multidrug-resistant tuberculosis (MDR-TB) regimens. The ophthalmic formulation (Vigamox) is widely used perioperatively in cataract surgery.

Approved indications

• Abdominal abscess
• Acute bacterial sinusitis
• Acute exacerbation of chronic bronchitis
• Bacterial conjunctivitis
• Bacterial infection due to Klebsiella pneumoniae
• Bacterial pneumonia
• Chlamydial pneumonia
• Complicated Skin and Skin Structure E. Coli Infection
• Complicated Skin and Skin Structure Infection
• Complicated Skin and Skin Structure Staphylococcus Aureus Infection
• Haemophilus Influenzae Chronic Bronchitis
• Haemophilus Parainfluenzae Chronic Bronchitis
• Haemophilus influenzae pneumonia
• Infection due to Enterobacteriaceae
• Infection due to Staphylococcus aureus
• Infection of skin AND/OR subcutaneous tissue
• Infectious disease of abdomen
• Klebsiella Pneumoniae Chronic Bronchitis
• Moraxella Catarrhalis Chronic Bronchitis
• Moraxella Catarrhalis Pneumonia

Boxed warnings

• WARNING: SERIOUS ADVERSE REACTIONS INCLUDING TENDINITIS, TENDON RUPTURE, PERIPHERAL NEUROPATHY, CENTRAL NERVOUS SYSTEM EFFECTS AND EXACERBATION OF MYASTHENIA GRAVIS Fluoroquinolones, including moxifloxacin hydrochloride, have been associated with disabling and potentially irreversible serious adverse reactions that have occurred together [see Warnings and Precautions (5.1) ] , including: 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) ] Discontinue moxifloxacin hydrochloride immediately and avoid the use of fluoroquinolones, including moxifloxacin hydrochloride, in patients who experience any of these serious adverse reactions [see Warnings and Precautions (5.1) ]. Fluoroquinolones, including moxifloxacin hydrochloride, may exacerbate muscle weakness in patients with myasthenia gravis. Avoid moxifloxacin hydrochloride in patients with known history of myasthenia gravis [see Warnings and Precautions (5.5) ]. Because fluoroquinolones, including moxifloxacin hydrochloride, have been associated with serious adverse reactions [see Warnings and Precautions (5.1 to 5.14) ] , reserve moxifloxacin hydrochloride for use in patients who have no alternative treatment options for the following indications: Acute bacterial sinusitis [see Indications and Usage (1.6) ] Acute bacterial exacerbation of chronic bronchitis [see Indications and Usage (1.7) ] WARNING: SERIOUS ADVERSE REACTIONS INCLUDING TENDINITIS, TENDON RUPTURE, PERIPHERAL NEUROPATHY, CENTRAL NERVOUS SYSTEM EFFECTS and EXACERBATION OF MYASTHENIA GRAVIS See full prescribing information for complete boxed warning Fluoroquinolones, including moxifloxacin hydrochloride, have been associated with disabling and potentially irreversible serious adverse reactions that have occurred together (5.1) including: Tendinitis and tendon rupture (5.2) Peripheral Neuropathy (5.3) Central nervous system effects (5.4) Discontinue moxifloxacin hydrochloride immediately and avoid the use of fluoroquinolones, including moxifloxacin hydrochloride, in patients who experience any of these serious adverse reactions (5.1) Fluoroquinolones, including moxifloxacin hydrochloride, may exacerbate muscle weakness in patients with myasthenia gravis. Avoid moxifloxacin hydrochloride in patients with known history of myasthenia gravis (5.5) . Because fluoroquinolones, including moxifloxacin hydrochloride, have been associated with serious adverse reactions (5.1 to 5.14) , reserve moxifloxacin hydrochloride for use in patients who have no alternative treatment options for the following indications: Acute bacterial sinusitis (1.6) Acute bacterial exacerbation of chronic bronchitis (1.7)

Common side effects

• Nausea
• Diarrhea
• Headache
• Dizziness

Serious adverse events

• Nausea (discontinuation)
• Rash (discontinuation)
• Diarrhea (discontinuation)
• Dizziness (discontinuation)
• Pyrexia (discontinuation)
• Vomiting (discontinuation)
• Tendinopathy and Tendon Rupture
• QT Prolongation
• Hypersensitivity Reactions
• Clostridium difficile-Associated Diarrhea

Key clinical trials

• Risk of Acute Liver Injury in Users of Antimicrobials in the HealthCore Integrated Research Database Population (N/A)
• Microbiome Effect of Omadacycline on Healthy Volunteers (Phase 1)
• A Single-centre, Randomised, Double-blind, Placebo-controlled, Four Way Crossover Phase I Study to Investigate the Effect on QT/QTc Interval of a Single Dose of Intravenous Ceftazidime NXL104 (3000/20 (Phase 1)
• A 2 PART STUDY IN HEALTHY SUBJECTS: PART A: A MULTIPLE DOSE, RANDOMIZED, PLACEBO CONTROLLED STUDY TO EVALUATE THE SAFETY AND TOLERABILITY OF SUPRA-THERAPEUTIC DOSES OF RO4602522; PART B: A MULTIPLE-DO (Phase 1)
• A Pan-Ultrashort Regimen for Drug-susceptible and Drug-resistant Pulmonary Tuberculosis: A Multi-Center Randomized Controlled Trial (Phase 3)
• A Phase 1, Double-Blinded, Placebo- and Active-Controlled, Randomized Study to Investigate the Potential of Soticlestat to Prolong the QTc Interval in Healthy Adult Participants (Phase 1)
• A Study to Assess the Effect of Etavopivat on Cardiac Repolarisation in Healthy Participants (Phase 1)
• A Randomized, Double-Blind, Placebo- and Positive-Controlled (Moxifloxacin), Parallel Study With a Nested Crossover to Assess the Effect of Multiple Oral Therapeutic and Supratherapeutic Doses of BIIB (Phase 1)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Avelox CI brief — competitive landscape report
• Avelox updates RSS · CI watch RSS
• Bayer AG portfolio CI