Moxifloxacin

Oral Antibiotics

Drug class: Fluoroquinolone; Quinolone antibiotic belongs to a subclass of fluoroquinolone antibiotics and is the 4^th generation.

Moxifloxacin (AVELOX)（中文：莫西沙星）

Common Strengths

• Tablet: 400 mg
• Infusion: 400 mg/250 mL
• Eye drops 0.5% w/v

Drug Trade Names

• Avelox
• Vigamox

Drug Usage

Moxifloxacin is a 4^th generation fluoroquinolone antibiotic used to treat various bacterial infections, including:

• Acute bacterial sinusitis
• Acute bacterial exacerbation of chronic bronchitis
• Community-acquired pneumonia
• Complicated skin infection
• Intra-abdominal infection
• Treatment and prevention of Plague (treatment and prophylaxis)

Mechanism of Action

Moxifloxacin works by inhibiting bacterial DNA replication. It binds to DNA gyrase and topoisomerase IV, essential enzymes for bacterial DNA replication, effectively stopping bacterial growth and reproduction.

Route of Administration

• Oral (Tablets)
• Intravenous (IV)
• Ophthalmic (Eye drops)

Dosage

• Normal Adult Dosage: 400 mg once daily for 5 to 21 days depending on the infection type.
• Renal Dosing:
  • No dose adjustment is required for eGFR ≥30 mL/min.
  • For eGFR <30 mL/min, dosing should be cautious and may involve extending the interval.

Side Effects

Frequency	Adverse reactions
Common Side Effects	Nausea
	Diarrhea
	Dizziness
	Headache
Serious Side Effects	Tendon rupture or tendinitis especially in older adults or those on corticosteroids.
	Peripheral neuropathy
	QT prolongation (risk of irregular heartbeat)
	CNS effects (e.g. seizures, hallucinations)

Pharmacokinetics

• The elimination half-life of moxifloxacin ranges from approximately 11.4 to 15.2 hours in healthy adults, supporting once-daily dosing regimens.
• Onset Time and Duration: Moxifloxacin typically starts working within hours, but noticeable improvement may take 2 to 3 days depending on the infection.

Drug Precautions

Pregnancy

Safety during pregnancy is unclear; use only if benefits outweigh risks.

Breastfeeding

Limited data; consult healthcare provider before use.

Children and Elderly

Not established for pediatric use; caution in elderly due to increased risk of tendon damage and renal issues.

Drug Monitoring Items

• Monitor renal function, especially in patients with existing kidney disease or those taking other medications that affect renal function.
• Blood glucose levels should be regularly checked in diabetic patients due to the risk of hypoglycemia
• ECG Monitoring: Moxifloxacin can cause significant heart rhythm changes. Baseline ECG should be taken, followed by monitoring every three months or after any new medications that may prolong QT
• Patients should be monitored for any signs of tendon pain or injury

Drug Interactions

• Antacids containing aluminum or magnesium (should be taken at least 4 hours apart)
• Caution with medications that prolong QT interval (e.g., antiarrhythmics)
• Anticoagulants like warfarin (may increase bleeding risk)

FAQ

How should I take the tablet?

Take moxifloxacin by mouth with or without food, usually once daily as directed by your healthcare provider.

What should I avoid while taking?

For optimal results, it is advisable to adhere to the timing for taking antacids, iron supplements, or multivitamins:

• 2 hours before taking moxifloxacin
• 2 hours after taking moxifloxacin

What happens if I miss a dose?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and resume your regular schedule. Do not double up on doses.