Moxifloxacin

Last Updated June 10, 2016

Trade Names

Avelon, Moxibay, Avebact, DRL Moxifloxacin, Litares, Numoxx

Drug Classification

Fluoroquinolone broad-spectrum antimicrobial

Formulations

400 mg tablets; 250 mL intravenous solution containing 400 mg moxifloxacin

Indications and Pharmacology

Indication: treatment of infections caused by susceptible bacterial strains; used to treat lower respiratory tract infections, acute sinusitis, and skin infections. Used in treatment of multidrug-resistant tuberculosis in combination with other second-line drugs; more active against tuberculosis than other fluoroquinolones and is thus preferred over other fluoroquinolones.

Mechanism of action: inhibition of topoisomerase II and IV enzymes, disrupting bacterial DNA replication, transcription, repair, recombination.

Pharmacokinetics: readily absorbed from gastrointestinal tract and widely distributed throughout body; C_max 4.5 ± 0.53 μg/mL, T_max 1-3 hrs, half-life about 12 hours. Metabolized via glucuronide and sulphate conjugation.

Dosage

Adult Dose: 400 mg once daily oral dosing; 400 mg daily infused over 60-minute intravenous dosing (see Warnings).

Oral dose may be taken with or without food, but fluids are encouraged.*

Use in Renal or Hepatic Insufficiency: 

• No adjustments needed for renal insufficiency, including those requiring dialysis
• No adjustments needed for hepatic insufficiency; use caution in patients with moderate to severe hepatic insufficiency due to potential for QT prolongation.

Use in Pregnancy and Breastfeeding: US Pregnancy Category C; use only if benefits outweigh potential risk to the foetus. May be excreted in breast milk, with potential for serious adverse reactions in breast-fed infants. Some recommend caution in pregnancy.*

Use in Children: 7.5-10 mg/kg/day (maximum 400 mg).*

Used in children > 8 years of age.*

Warnings

Contraindicated in patients with hypersensitivity to moxifloxacin or any other quinolone antimicrobials.

Use with caution in patients with moderate to severe hepatic insufficiency.

Associated with increased risk of tendinitis and tendon rupture, especially in patients > 60 yrs, taking corticosteroid drugs, or with kidney, heart, or lung transplants.^†

Avoid use in those with myasthenia gravis, due to reports of serious adverse events, including ventilator support and death.^† Reported prolongation of QT interval of the electrocardiogram; not recommended in patients with known QT prolongation, uncorrected hypokalemia or receiving class IA or class III antiarrhythmics.

Anaphylactic and/or hypersensitivity reactions may occur after the first dose; fever, rash, severe dermatologic reactions, vasculitis, arthralgia, myalgia, serum sickness, allergic pneumonitis, renal toxicity, hepatic toxicity, anaemia, thrombocytopenia, leukopenia, and other haematologic abnormalities may occur after multiple doses.^†

Reports of other reactions and adverse events including central nervous system effects, Clostridium difficile–associated diarrhoea, peripheral neuropathy, prolongation of the QT interval, musculoskeletal disorders in paediatric patients, blood glucose disturbances, photosensitivity/phototoxicity, development of drug-resistant bacteria.^†

Avoid rapid or bolus intravenous administration, give as slow infusion over 60 minutes. Do not mix with other medications in IV bag or line.*

Drug–Drug Interactions

Decreased absorption of moxifloxacin with multivalent cation-containing products (eg, magnesium/aluminium antacids, sucralfate, didanosine chewable/buffered tablets or paediatric powder, highly buffered drugs, products containing calcium, zinc, or iron); should be taken 4 hours before or 8 hours after use of these agents.*

Possible increased concentration or effects of concomitant warfarin; monitor international normalised ratio and prothrombin time.*

Possible increased risk of central nervous system stimulation and convulsive seizures with concomitant nonsteroidal antiinflammatory.*

May increase QTc interval of electrocardiogram with concomitant Class IA or Class III antiarrhythmics.*

Considerations for Special Populations

Geriatric: increased risk of severe hepatotoxicity, tendinopathy, especially with concomitant corticosteroid use, and prolongation of QT interval.^†

Hepatic insufficiency: use caution in patients with moderate to severe hepatic insufficiency.^†

QT interval: not recommended in patients with known QT prolongation, uncorrected hypokalemia or receiving class IA or class III antiarrhythmics; caution should be used in patients receiving other drugs known to prolong the QT interval or with congenital QT prolongation.^†

See above for pregnancy and lactation.^†

Adverse Effects

Nausea, diarrhoea, abnormal liver function tests, vomiting, rash, abdominal pain, pain in extremities, convulsions, increased intracranial pressure, toxic psychosis, central nervous system events (headache, nervousness, agitation, restlessness, drowsiness, insomnia, anxiety, nightmares, paranoia, dizziness, confusion, tremor, hallucination, depression, suicidal thoughts or acts), hypersensitivity reactions, cardiac disturbances (QT prolongation and torsades de points), hepatic necrosis, interstitial nephritis, blood disorders, pseudomembranous colitis, peripheral neuropathy, tendonitis and tendon ruptures, phototoxicity.^†

Seizures may occur in patients with underlying central nervous system disease.*

*Information from Aurum Institute Drugs on the Go.
^†Information from US Prescribing Information.