Comparative Pharmacology
Head-to-head clinical analysis: MAXITROL versus OZURDEX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MAXITROL versus OZURDEX.
MAXITROL vs OZURDEX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Maxitrol is a combination of dexamethasone (corticosteroid), neomycin (aminoglycoside antibiotic), and polymyxin B (polymyxin antibiotic). Dexamethasone suppresses inflammation by inhibiting phospholipase A2, reducing prostaglandin and leukotriene synthesis. Neomycin binds to bacterial 30S ribosomal subunit, causing misreading of mRNA and inhibiting protein synthesis. Polymyxin B disrupts bacterial cell membrane integrity by binding to lipopolysaccharides.
Dexamethasone, a potent corticosteroid, reduces inflammation by inhibiting multiple inflammatory cytokines including prostaglandins, leukotrienes, and interleukins. It suppresses the migration of polymorphonuclear leukocytes and reverses increased capillary permeability. The mechanism involves binding to the glucocorticoid receptor, leading to regulation of gene expression that reduces production of inflammatory mediators.
1-2 drops or 0.5-1 inch strip of ointment into the conjunctival sac every 4-6 hours; in severe cases, every 2-4 hours. Frequency may be reduced after improvement.
Single intravitreal implant of 0.7 mg (dexamethasone 700 mcg) in the affected eye; repeat dosing no sooner than 3 months after the prior implant.
None Documented
None Documented
Neomycin: 2–3 h (topical) but prolonged in renal impairment. Polymyxin B: 6–7 h (topical). Dexamethasone: 3–4 h (topical). Clinical: systemic absorption minimal with intact epithelium; half-life may be prolonged with corneal abrasion or inflammation.
In the vitreous humor, the half-life is approximately 5-7 months following intravitreal implant administration. Systemic half-life is negligible due to low systemic exposure.
Renal: neomycin 30–50%; polymyxin B <1%; dexamethasone <1%. Fecal: neomycin >50% (unabsorbed); polymyxin B >99% (unabsorbed); dexamethasone <5%. Biliary: negligible for all components.
Primarily hepatic metabolism via CYP3A4; metabolites excreted in feces (≈70%) and urine (≈30%). Less than 1% excreted as unchanged drug.
Category C
Category C
Ophthalmic Corticosteroid/Antibiotic Combination
Ophthalmic Corticosteroid