MAXAQUIN
Clinical safety rating: caution
Comprehensive clinical and safety monograph for MAXAQUIN (MAXAQUIN).
Fluoroquinolone antibiotic that inhibits bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, thereby interfering with DNA replication, transcription, repair, and recombination.
| Metabolism | Hepatic metabolism via glucuronidation and sulfation; minor CYP450 involvement. Excreted primarily unchanged in urine (40-60%) and feces (20-40%). |
| Excretion | Renal excretion of unchanged drug accounts for 70-80%; biliary/fecal elimination accounts for 20-30%. |
| Half-life | Terminal elimination half-life is approximately 12 hours (range 10-14 hours), supporting twice-daily dosing for systemic infections. |
| Protein binding | 30-40% bound to serum albumin. |
| Volume of Distribution | 1.5-2.0 L/kg, indicating extensive extravascular distribution. |
| Bioavailability | Oral: 90-100%. |
| Onset of Action | Oral: 1-2 hours; intravenous: immediate (within minutes for clinical effect). |
| Duration of Action | Approximately 12 hours, consistent with dosing interval of every 12 hours for most indications. |
400 mg orally once daily for 5-10 days; for complicated urinary tract infections, 400 mg orally once daily for 10-14 days.
| Dosage form | TABLET |
| Renal impairment | CrCl ≥30 mL/min: no adjustment; CrCl <30 mL/min or hemodialysis: 400 mg orally every 48 hours; peritoneal dialysis: 400 mg orally every 48 hours. |
| Liver impairment | No adjustment required for mild to moderate hepatic impairment; not studied in severe impairment, use with caution. |
| Pediatric use | Not recommended for patients <18 years of age due to risk of arthropathy. |
| Geriatric use | No specific dose adjustment; consider renal function and potential increased risk of tendon rupture; start at lower end of dosing range if renal impairment present. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for MAXAQUIN (MAXAQUIN).
| Breastfeeding | Fluoroquinolones are excreted in breast milk. M/P ratio not established for MAXAQUIN; avoid breastfeeding due to potential arthropathy in nursing infants. |
| Teratogenic Risk | Fluoroquinolones cross the placenta. In animal studies, no consistent teratogenicity observed but arthropathy reported in juvenile animals. Human data insufficient; use only if benefit outweighs risk. Avoid in first trimester if possible. |
| Fetal Monitoring |
■ FDA Black Box Warning
Fluoroquinolones, including MAXAQUIN, have been associated with an increased risk of tendinitis and tendon rupture in all ages. This risk is further increased in patients over 60 years of age, in patients taking corticosteroids, and in patients with kidney, heart, or lung transplants.
| Serious Effects |
["Hypersensitivity to lomefloxacin or any fluoroquinolone","History of tendinopathy or tendon rupture with fluoroquinolone use","Pregnancy (Category C; avoid due to arthropathy in animal studies)","Lactation (excreted in breast milk; avoid use in nursing mothers)","Children (<18 years of age) except for specific approved indications (e.g., inhalational anthrax)","Concomitant use with tizanidine (may result in severe hypotension and sedation)"]
| Precautions | ["Tendon damage: discontinue at first sign of tendon pain, swelling, or inflammation.","Exacerbation of myasthenia gravis: avoid use in patients with known history.","Neuropathy: peripheral neuropathy may occur rapidly; discontinue if symptoms develop.","CNS effects: may cause dizziness, confusion, and increased intracranial pressure; use with caution in patients with CNS disorders.","QT prolongation: avoid in patients with known QT prolongation, electrolyte abnormalities, or concurrent use of Class IA/III antiarrhythmics.","Hypersensitivity reactions: serious and occasionally fatal anaphylactic reactions have been reported.","Photosensitivity: avoid excessive sunlight or UV light.","Renal impairment: dose adjustment required for creatinine clearance <30 mL/min.","C. difficile-associated diarrhea: consider discontinuation if diarrhea occurs."] |
Loading safety data…
| Monitor for maternal adverse effects (tendonitis, QT prolongation). Fetal monitoring not required specifically, but consider fetal ultrasound if prolonged use. |
| Fertility Effects | No specific data on fertility effects. Fluoroquinolones may affect sperm motility in animal studies; clinical significance unknown. |