Comparative Pharmacology
Head-to-head clinical analysis: MAXITROL versus PRED G.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MAXITROL versus PRED G.
MAXITROL vs PRED-G
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.
Prednisolone acetate is a glucocorticoid that suppresses inflammation by inhibiting phospholipase A2, reducing prostaglandin and leukotriene synthesis; gentamicin sulfate is an aminoglycoside antibiotic that inhibits bacterial protein synthesis by binding to 30S ribosomal subunit.
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.
1 drop of the ophthalmic suspension (containing prednisolone acetate 1% and gentamicin sulfate 0.3%) into the affected eye(s) every 2-4 hours during the day, then taper as clinical signs improve. For severe disease, 1 drop every hour initially.
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.
The terminal elimination half-life of gentamicin (the active component) is approximately 2–3 hours in adults with normal renal function. In neonates, half-life is prolonged to 5–11 hours. The immunosuppressive component (prednisolone) has a half-life of 2–4 hours.
Renal: neomycin 30–50%; polymyxin B <1%; dexamethasone <1%. Fecal: neomycin >50% (unabsorbed); polymyxin B >99% (unabsorbed); dexamethasone <5%. Biliary: negligible for all components.
Renal excretion accounts for approximately 70% of elimination, with the remainder as unchanged drug in feces (20%) and biliary excretion (10%).
Category C
Category C
Ophthalmic Corticosteroid/Antibiotic Combination
Ophthalmic Corticosteroid/Antibiotic Combination