Moxifloxacin
A fluoroquinolone antibiotic used for pneumonia, skin and abdominal infections, and in some tuberculosis regimens.
Drug card
- Class
- Fluoroquinolone
- How it works
- Blocking DNA gyrase and topoisomerase IV, so bacteria cannot copy their DNA
- Used for
- Community-acquired pneumonia
- Skin and soft tissue infections
- Complicated abdominal infections
- Tuberculosis, in some regimens
- Known for
- Long QT interval
- Tendinitis and tendon rupture
- Its name
- -floxacin means a fluoroquinolone antibiotic
Study it as a flashcard, and it comes back before you forget it.
Mechanism of action
How does moxifloxacin work?
Blocks DNA gyrase and topoisomerase IV. Besides respiratory bacteria such as Streptococcus pneumoniae, it covers anaerobes such as Bacteroides fragilis. Its dose needs no change in kidney disease, and it has no licensed use for urinary infections.
Like other fluoroquinolones: Fluoroquinolones block DNA gyrase and topoisomerase IV, two bacterial type II topoisomerases (gyrase is topoisomerase II). The bacterium needs both to copy, transcribe and repair its DNA, so blocking them halts DNA replication and kills the cell: the drugs are bactericidal. Bacteria resist them mainly through gyrase mutations, a less permeable outer membrane or efflux pumps.
Uses
What is moxifloxacin used for?
- Community-acquired pneumonia
- Skin and soft tissue infections
- Complicated abdominal infections
- Tuberculosis, in some regimens
Side effects
Side effects of moxifloxacin
- Long QT intervalKnown forSerious
- Tendinitis and tendon ruptureKnown forSerious
- Nausea
- Diarrhea
- Headache
- Dizziness
- Peripheral neuropathySerious
- SeizuresSerious
- Mood changes and psychosisSerious
- Hepatitis and liver failureSerious
- Kidney inflammation or failureSerious
- Severe skin reactions (SJS, TEN)Serious
Known for marks what an exam expects you to know it for.
Watch for
Cautions and what sets it apart
- Avoid in known QT prolongation, uncorrected low potassium, and with class IA or III antiarrhythmics.
- Liver cirrhosis: watch the ECG, as the QT interval may lengthen more.
- Space doses apart from antacids, iron, zinc and other products containing metal ions.
Good to know: Unlike ciprofloxacin, it covers anaerobes and treats complicated abdominal infections without metronidazole. CDC lists it in regimens for both drug-sensitive and drug-resistant tuberculosis.
Remember it
A way to remember it
STAMP
- S
- Sugar swings: low or high blood sugar
- T
- Tendinitis and tendon rupture
- A
- Aortic aneurysm or dissection
- M
- Myasthenia gravis made worse
- P
- Peripheral neuropathy
Fluoroquinolones can leave a STAMP on the body: these are the serious harms in their label warnings.
Written for biofideX
Its name
-floxacin means fluoroquinolone antibiotic
WHO's stem is -oxacin (quinolones); -floxacin is its fluorinated subgroup: ciprofloxacin, levofloxacin, moxifloxacin. Nalidixic acid, the parent quinolone, has no stem.
- Every drug name stem
Its class
Fluoroquinolones
Other fluoroquinolones with a card:
Easily mixed up with topoisomerase II inhibitors and tetracyclines.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- Moxifloxacin tablets: label (DailyMed)
- Moxifloxacin (NCI Thesaurus)
- Treatment for Drug-Resistant Tuberculosis Disease (CDC)
- Treatment for Drug-Susceptible Tuberculosis Disease (CDC)
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Antibiotics: DNA, folate and tuberculosis
Moxifloxacin is one of 11 drugs practiced together here: their classes, how they work, what they treat and what they're known for.
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