dexamethasone/neomycin/polymyxin (Maxitrol, Dexasporin)
Dosing and uses of Maxitrol, Dexasporin (dexamethasone/neomycin/polymyxin)
Adult dosage forms and strengths
dexamethasone/neomycin/polymyxin
ophthalmic ointment
- (0.1%/3.5g/10,000units)/g (3.5g)
ophthalmic suspension
- (0.1%/3.5g/10,000units)/mL (5mL)
Inflammatory Ocular Conditions/Infections
Indicated for steroid-responsive inflammatory eye conditions in which dexamethasone is indicated & where bacterial infection or a risk of bacterial infection exists
Ophthalmic suspension: Instill 1-2 gtt to affected eye(s) q4-6hr; may use hourly in severe disease follow by taper for discontinuation
Ophthalmic ointment: Apply ribbon (~0.5-in) to affected eye(s) in conjunctival sac q4-6hr or as adjunct to suspension
Patient should be re-evaluated if no improvement after 2 days
Pediatric dosage forms and strengths
dexamethasone/neomycin/polymyxin
ophthalmic ointment
- (0.1%/0.35%/10,000units)/g (3.5g)
ophthalmic suspension
- (0.1%/0.35%/10,000units)/mL (5mL)
Inflammatory Ocular Conditions
Indicated for steroid-responsive inflammatory eye conditions in which dexamethasone is indicated & where bacterial infection or a risk of bacterial infection exists
Ophthalmic suspension: Instill 1-2 gtt to affected eye(s) q4-6hr; may use hourly in severe disease follow by taper for discontinuation
Ophthalmic ointment: Apply ribbon (~0.5-in) to affected eye(s) in conjunctival sac q4-6hr or as adjunct to suspension
Patient should be re-evaluated if no improvement after 2 days
Maxitrol, Dexasporin (dexamethasone/neomycin/polymyxin) adverse (side) effects
Frequency not defined
Blurred vision
Cataract
Raised intraocular pressure
Stinging
Conjunctival hemorrhage
Glaucoma
Vitreous detachment
Hives
Rash
Itching
Eye pain
Warnings
Contraindicatons
Hypersensitivity
Viral diseases of the cornea and conjunctiva, including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, and varicella
Mycobacterial infection of the eye and fungal diseases of ocular structures
Cautions
Monitor intraocular pressure if used >10 days
Prolonged use of topical anti-bacterial agents may give rise to overgrowth of nonsusceptible organisms including fungi
Prolonged use of corticosteroids may result in glaucoma with damage to the optic nerve, defects in visual acuity and fields of vision, and in posterior subcapsular cataract formation
Prolonged use may also suppress the host immune response and thus increase the hazard of secondary ocular infections
Various ocular diseases and long-term use of topical corticosteroids have been known to cause corneal and scleral thinning, possibly leading to perforation
Acute purulent infections of the eye may be masked or activity enhanced by the presence of corticosteroid medication
Pregnancy and lactation
Pregnancy category: C
Lactation: Unknown if excreted in breastmilk; minimal systemic absorption with ophthalmic administration
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Maxitrol, Dexasporin (dexamethasone/neomycin/polymyxin)
Mechanism of action
Neomycin inhibits bacterial protein synthesis by binding to 30S ribosomal subunits
Polymyxin B alters permeability of cell membranes, which in turn causes intracellular products to leak
Dexamethasone prevents/reduces irritation & swelling by suppressing normal immune response, decreasing inflammatory mediators and reverses capillary permeability
