Neomycin (EENT) (Monograph)

Brand name: Casporyn HC
Drug class: Antibacterials
ATC class: S01AA03
VA class: OT101
CAS number: 1405-10-3

Introduction

Antibacterial; aminoglycoside antibiotic.

Uses for Neomycin (EENT)

Bacterial Ophthalmic Infections

Used in fixed combination with other anti-infectives (i.e., polymyxin B and bacitracin; polymyxin B and gramicidin) for topical treatment of superficial infections of the eye (e.g., conjunctivitis, keratitis, keratoconjunctivitis, blepharitis, blepharoconjunctivitis) caused by susceptible bacteria.

Mild, acute bacterial conjunctivitis often resolves spontaneously without anti-infective treatment. Although topical ophthalmic anti-infectives may shorten time to resolution and reduce severity and risk of complications, avoid indiscriminate use of topical anti-infectives. Treatment of acute bacterial conjunctivitis generally is empiric; use of a broad-spectrum topical ophthalmic antibacterial usually recommended. In vitro staining and/or cultures of conjunctival material may be indicated in management of recurrent, severe, or chronic purulent conjunctivitis or when acute conjunctivitis does not respond to initial empiric topical treatment.

Because bacterial keratitis may be associated with subsequent loss of vision as the result of corneal scarring or topographic irregularities and because untreated or severe bacterial keratitis may result in corneal perforation with potential for endophthalmitis and possible loss of the eye, optimal management involves rapid evaluation and diagnosis, timely initiation of treatment, and appropriate follow-up. Treatment of community-acquired bacterial keratitis generally is empiric; use of a broad-spectrum topical ophthalmic antibacterial usually recommended. Subconjunctival anti-infectives may be necessary if scleral spread or perforation is imminent. In vitro staining and/or cultures of corneal material are indicated in management of keratitis involving corneal infiltrates that are central, large, and extend to the middle to deep stroma; when keratitis is chronic or unresponsive to broad-spectrum topical anti-infective treatment; or when atypical features suggest fungal, amebic, or mycobacterial infection.

Bacterial Otic Infections

Used in fixed combination with colistin and hydrocortisone acetate or in fixed combination with polymyxin B and hydrocortisone for topical treatment of superficial infections of the external auditory canal (otitis externa) caused by susceptible bacteria. Also used for topical treatment of infections of mastoidectomy or fenestration cavities caused by susceptible bacteria.

Diffuse, uncomplicated acute otitis externa in otherwise healthy patients usually treated initially with topical therapy (e.g., otic anti-infective or antiseptic with or without an otic corticosteroid). Supplement with systemic anti-infective therapy if patient has a medical condition that could impair host defenses (e.g., diabetes mellitus, HIV infection) or if infection has spread into pinna, skin of the neck or face, or into deeper tissues such as occurs with malignant otitis externa. Malignant otitis externa is an invasive, potentially life-threatening infection, especially in immunocompromised patients, and requires prompt diagnosis and treatment with systemic anti-infectives.

Ocular Inflammation

Fixed-combination ophthalmic preparations containing neomycin, polymyxin B, and dexamethasone or fixed-combination ophthalmic preparations containing neomycin, polymyxin B, bacitracin, and hydrocortisone or hydrocortisone acetate are used for topical treatment of corticosteroid-responsive ocular conditions when a corticosteroid is indicated and superficial bacterial ocular infection or risk of such infection exists.

Although manufacturers state that use of fixed-combination ophthalmic preparations containing anti-infectives and a corticosteroid may be indicated in ocular inflammatory conditions when risk of superficial ocular infection is high or when potentially dangerous numbers of bacteria are expected to be present in the eye, experts state avoid use of such preparations in patients with bacterial conjunctivitis because of risk of potentiating the infection.

Consider that use of fixed-combination ophthalmic preparations containing anti-infectives and a corticosteroid may mask clinical signs of bacterial, fungal, or viral infections; prevent recognition of ineffectiveness of the anti-infectives; and/or increase IOP. (See Use of Fixed Combinations Containing Corticosteroids under Cautions.)

Neomycin (EENT) Dosage and Administration

Administration

Ophthalmic Administration

Fixed combination of neomycin, polymyxin B, and bacitracin: Apply topically to eye as an ophthalmic ointment.

Fixed combination of neomycin, polymyxin B, and gramicidin: Apply topically to eye as an ophthalmic solution.

Fixed combination of neomycin, other anti-infectives (i.e., polymyxin B with or without bacitracin), and a corticosteroid (i.e., dexamethasone, hydrocortisone, or hydrocortisone acetate): Apply topically to eye as ophthalmic ointments or suspensions.

For topical ophthalmic use only; do not inject subconjunctivally or directly into anterior chamber of the eye.

Avoid contaminating container tip with material from eye, eyelids, fingers, or other source.

Otic Administration

Fixed combination of neomycin, colistin, and hydrocortisone acetate: Apply topically into ear canal as an otic suspension.

Fixed combination of neomycin, polymyxin B, and hydrocortisone: Apply topically into ear canal as an otic solution or suspension.

Otic preparations are for topical otic use only; do not use in the eyes.

Clean and dry ear canal prior to administration.

Shake otic suspensions well prior to each use.

Lie with the affected ear upward. Instill appropriate amount of otic solution or suspension into ear; maintain this position for 5 minutes to facilitate penetration into ear canal. Repeat procedure for the opposite ear if necessary.

If ear canal is narrow or edematous and there are concerns that drug delivery might be impeded, consider inserting cotton wick into ear canal and saturating it with the otic preparation. Manufacturers state keep wick moist by adding additional otic solution or suspension every 4 hours and replace wick once every 24 hours. Experts state that wick unnecessary after ear canal edema subsides, which may occur within 24 hours or a few days after topical treatment initiated.

Avoid contaminating container tip with material from ear, fingers, or other source.

Dosage

Available as neomycin sulfate; dosage expressed in terms of the base.

Pediatric Patients

Bacterial Otic Infections

Otic

Neomycin, colistin, and hydrocortisone acetate in children ≥1 year of age (otic suspension): Instill 4 drops in affected ear(s) 3 or 4 times daily for up to 10 days.

Neomycin, polymyxin B, and hydrocortisone in children ≥2 years of age (otic solution or suspension): Instill 3 drops in affected ear(s) 3 or 4 times daily for up to 10 days.

Optimal duration of topical treatment of acute otitis externa not determined, but 7–10 days usually recommended. Appropriate treatment should result in improvement in symptoms (otalgia, pruritus, fullness) within 48–72 hours, although resolution of symptoms may take up to 2 weeks.

Ocular Inflammation

Ophthalmic

Neomycin, polymyxin B, and dexamethasone in children ≥2 years of age (ophthalmic suspension): Instill 1 or 2 drops in conjunctival sac of affected eye(s) up to 4–6 times daily. In severe disease, instill 1 or 2 drops every hour initially, then taper dosage by decreasing frequency of administration as inflammation subsides.

If no improvement after 48 hours, reevaluate patient. (See Use of Fixed Combinations Containing Corticosteroids under Cautions.)

Adults

Bacterial Ophthalmic Infections

Ophthalmic

Neomycin, polymyxin B, and bacitracin (ophthalmic ointment): Apply to affected eye(s) every 3 or 4 hours for 7–10 days, depending on severity of infection.

Neomycin, polymyxin B, and gramicidin (ophthalmic solution): Instill 1 or 2 drops in affected eye(s) every 4 hours for 7–10 days. For severe infections, may instill up to 2 drops every hour.

Usual duration of topical anti-infective treatment for bacterial conjunctivitis is 5–10 days; 5–7 days usually adequate for mild bacterial conjunctivitis.

Bacterial Otic Infections

Otic

Neomycin, colistin, and hydrocortisone (otic suspension): Instill 5 drops in affected ear(s) 3 or 4 times daily for up to 10 days.

Neomycin, polymyxin B, and hydrocortisone (otic solution or suspension): Instill 4 drops in affected ear(s) 3 or 4 times daily for up to 10 days.

Ocular Inflammation

Ophthalmic

Neomycin, polymyxin B, and dexamethasone (ophthalmic ointment): Apply approximately 1.25 cm (½ inch) of ointment in conjunctival sac of affected eye(s) up to 3 or 4 times daily.

Neomycin, polymyxin B, and dexamethasone (ophthalmic suspension): Instill 1 or 2 drops in conjunctival sac of affected eye(s) up to 4–6 times daily. In severe disease, instill 1 or 2 drops every hour initially, then taper dosage by decreasing frequency of administration as inflammation subsides.

Neomycin, polymyxin B, bacitracin, and hydrocortisone or hydrocortisone acetate (ophthalmic ointment): Apply to affected eye(s) every 3 or 4 hours, depending on severity of condition.

If no improvement after 48 hours, reevaluate patient. (See Use of Fixed Combinations Containing Corticosteroids under Cautions.)

Prescribing Limits

Pediatric Patients

Bacterial Otic Infections

Otic

Neomycin, colistin, and hydrocortisone acetate in children ≥1 year of age: Maximum 10 days of therapy.

Neomycin, polymyxin B, and hydrocortisone in children ≥2 years of age: Maximum 10 days of therapy.

Adults

Bacterial Otic Infections

Otic

Neomycin, colistin, and hydrocortisone acetate: Maximum 10 days of therapy.

Neomycin, polymyxin B, and hydrocortisone: Maximum 10 days of therapy.

Special Populations

No special population dosage recommendations.

Cautions for Neomycin (EENT)

Contraindications

Fixed combinations of neomycin and other anti-infectives (ophthalmic): Hypersensitivity to any ingredient in the formulation.
Fixed combinations of neomycin, other anti-infectives, and dexamethasone, hydrocortisone, or hydrocortisone acetate (ophthalmic): Hypersensitivity to any ingredient in the formulation. Also, viral diseases of the cornea and conjunctiva (e.g., epithelial herpes simplex keratitis [dendritic keratitis], vaccinia, varicella), mycobacterial infections of the eye, or fungal diseases of ocular structures.
Fixed combinations of neomycin, colistin, and hydrocortisone acetate (otic): Hypersensitivity to any ingredient in the formulation. Also, known or suspected viral infections of external ear canal (e.g., herpes simplex, varicella zoster).
Fixed combinations of neomycin, polymyxin B, and hydrocortisone (otic): Hypersensitivity to any ingredient in the formulation. Also, known or suspected viral infections of external ear canal (e.g., herpes simplex, vaccinia, varicella zoster).

Warnings/Precautions

Sensitivity Reactions

Hypersensitivity Reactions

Local irritation and allergic reactions reported; more serious hypersensitivity reactions, including anaphylaxis, reported rarely .

Topical anti-infectives, particularly neomycin, may cause cutaneous sensitization.

During long-term use, periodically examine patient for signs of sensitization.

Ophthalmic preparations: Sensitivity may manifest as rash, pruritus, edema of the conjunctiva and eyelid, conjunctival erythema, or failure to heal.

Otic preparations: Sensitivity may manifest as low-grade reddening with swelling, dry scaling, pruritus, or failure to heal.

If signs or symptoms of sensitivity occur, discontinue the drug. Symptoms usually subside quickly after preparation discontinued.

Patients allergic to one fixed-combination preparation should avoid preparations containing any of the component drugs. Cross-allergenicity occurs among the aminoglycosides; patients allergic to neomycin may also be allergic to other aminoglycosides (e.g., gentamicin, paromomycin, streptomycin).

Sulfite Sensitivity

Some fixed-combination otic preparations contain potassium metabisulfite, a sulfite that can cause allergic-type reactions (including anaphylaxis and life-threatening or less severe asthmatic episodes) in certain susceptible individuals.

Superinfection

Prolonged use may result in overgrowth of nonsusceptible organisms, including fungi. If superinfection occurs, discontinue the neomycin preparation and institute appropriate therapy.

Resistance to neomycin or other anti-infectives in fixed-combination preparations may develop.

Precautions Related to Ophthalmic Administration

Bacterial keratitis has developed in patients who inadvertently contaminated the multiple-dose container of their ophthalmic preparation; in most reported cases, concurrent corneal disease or disruption of ocular epithelial surface was present.

Vision may be temporarily blurred after administration of topical ophthalmic preparations. Take care in operating machinery or driving a motor vehicle.

Some manufacturers caution that ophthalmic ointments may delay healing.

Precautions Related to Otic Administration

Otic preparations containing neomycin, colistin, and hydrocortisone acetate: Use with caution in patients with perforated tympanic membrane.

Otic preparations containing neomycin, polymyxin B, and hydrocortisone: Do not use in patients with perforated tympanic membrane.

Neomycin, especially with prolonged use, can induce permanent sensorineural hearing loss due to cochlear damage, mainly destruction of hair cells in the organ of Corti.

Use otic preparations containing neomycin only under close clinical observation; do not use for longer than 10 consecutive days.

If used to control secondary infection in chronic otitis externa, consider that skin in this condition is more liable than normal skin to become sensitized to many substances, including neomycin. (See Hypersensitivity Reactions under Cautions.)

If otic infection not improved after 1 week of treatment, obtain cultures to guide treatment.

Use of Fixed Combinations Containing Corticosteroids

When ophthalmic or otic preparations containing polymyxin B in fixed combination with other anti-infectives and a corticosteroid (i.e., dexamethasone, hydrocortisone, hydrocortisone acetate) are used, consider cautions, precautions, and contraindications associated with EENT corticosteroids.

Provide initial prescriptions for fixed-combination ophthalmic preparations containing a corticosteroid or renewal prescriptions (beyond 8 g of ophthalmic ointment or beyond 20 mL of ophthalmic suspension) only after examining patient with slit lamp microscopy and, when appropriate, fluorescein staining.

Reevaluate patient if eye pain or inflammation persists for >48 hours or becomes aggravated.

Prolonged use of ophthalmic preparations containing a corticosteroid may result in glaucoma, with optic nerve damage, defects in visual acuity and fields of vision, and posterior subcapsular cataract formation. If used for ≥10 days, monitor IOP regularly, even though monitoring may be difficult in children and uncooperative patients. Use with caution in patients with glaucoma; check IOP frequently in such patients.

Use after cataract surgery may delay healing and increase incidence of bleb formation.

Corneal and scleral thinning reported with various ocular diseases and with long-term use of topical ophthalmic corticosteroids. Use in patients with thin corneal and scleral tissue may result in perforation.

Prolonged use may suppress host responses and increase risk of secondary ocular infections. Use in patients with acute purulent conditions of the eye may mask infection or enhance existing infection.

May prolong course and exacerbate severity of many viral infections of the eye (including herpes simplex). Use great caution in patients with herpes simplex; frequent slit lamp microscopy recommended.

Consider possibility of fungal infections of the cornea after prolonged use, especially in patients with persistent corneal ulceration. Perform fungal cultures when appropriate.

Specific Populations

Pregnancy

Not known whether ophthalmic preparations containing neomycin can cause fetal harm when administered to pregnant women.

Neomycin and other anti-infectives (ophthalmic): Use during pregnancy only if clearly needed.

Neomycin, other anti-infectives, and dexamethasone, hydrocortisone, or hydrocortisone acetate (ophthalmic): Use during pregnancy only if potential benefits justify potential risks to fetus.

Neomycin, colistin, and hydrocortisone acetate (otic): Use during pregnancy only if potential benefits justify potential risks to fetus. Although aminoglycosides can cause congenital deafness in humans if administered during pregnancy, manufacturers state that clinically important systemic concentrations of neomycin not anticipated when otic preparations containing neomycin are used as directed.

Neomycin, polymyxin B, and hydrocortisone (otic): Use during pregnancy only if potential benefits justify potential risks to fetus.

Lactation

Not known whether neomycin is distributed into milk.

Neomycin and other anti-infectives (ophthalmic): Use with caution.

Neomycin, polymyxin B, and dexamethasone (ophthalmic): Use with caution.

Neomycin, polymyxin B, bacitracin, and hydrocortisone or hydrocortisone acetate (ophthalmic): Discontinue nursing or the drug, taking into account importance of the drug to the woman.

Neomycin, colistin, and hydrocortisone acetate (otic): Use with caution.

Neomycin, polymyxin B, and hydrocortisone (otic): Use with caution.

Pediatric Use

Neomycin, polymyxin B, and bacitracin or gramicidin (ophthalmic): Safety and efficacy not established in pediatric patients.

Neomycin, polymyxin B, and dexamethasone (ophthalmic): Safety and efficacy of the suspension not established in children <2 years of age; safety and efficacy of the ointment not established in pediatric patients.

Neomycin, polymyxin B, bacitracin, and either hydrocortisone or hydrocortisone acetate (ophthalmic): Safety and efficacy not established in pediatric patients.

Neomycin, colistin, and hydrocortisone acetate (otic): Safety and efficacy not established in children <1 year of age.

Neomycin, polymyxin B, and hydrocortisone (otic): Most manufacturers state safety and efficacy not established in children <2 years of age because of insufficient data. One manufacturer states safety and efficacy have been established in pediatric patients and does not specify an age range.

Geriatric Use

Neomycin, polymyxin B, and gramicidin (ophthalmic): Clinical data insufficient to determine whether geriatric patients respond differently than younger adults; other clinical experience has not identified differences in response.

Neomycin, polymyxin B, and dexamethasone (ophthalmic): No overall differences in safety or efficacy relative to younger patients.

Neomycin, polymyxin B, bacitracin, and hydrocortisone acetate (ophthalmic): No overall differences in safety or efficacy relative to younger adults.

Neomycin, colistin, and hydrocortisone acetate (otic): No overall differences in safety or efficacy relative to younger adults.

Neomycin, polymyxin B, and hydrocortisone (otic): Clinical data insufficient to determine whether geriatric patients respond differently than younger patients; other clinical experience has not identified differences in response.

Common Adverse Effects

Local irritation and allergic reactions.

Neomycin (EENT) Pharmacokinetics

Absorption

Bioavailability

Absorbed into the aqueous humor following topical instillation onto the eye in rabbits; absorption is greatest when cornea is abraded.

Absorbed through the ear in dogs, absorption greatest when tympanic membrane is perforated.

Stability

Storage

Ophthalmic

Ointment

Neomycin, polymyxin B, and bacitracin: 15–25°C.

Neomycin, polymyxin B, and dexamethasone: 2–25°C. Contains methylparaben and propylparaben as preservatives.

Neomycin, polymyxin B, bacitracin, and hydrocortisone or hydrocortisone acetate: 15–25°C.

Solution

Neomycin, polymyxin B, and gramicidin: 15–25°C; protect from light. Contains thimerosal as a preservative.

Suspension

Neomycin, polymyxin B, and dexamethasone: 8–25°C. Contains benzalkonium chloride as a preservative.

Otic

Solution

Neomycin, polymyxin B, and hydrocortisone: 15–25°C. Contains potassium metabisulfite as a preservative (see Sulfite Sensitivity under Cautions).

Suspension

Neomycin, colistin, and hydrocortisone acetate: 20–25°C.

Neomycin, polymyxin B, and hydrocortisone: 15–25°C. Contains thimerosal as a preservative.

Actions and Spectrum

Aminoglycoside antibiotic obtained from cultures of Streptomyces fradiae.
Usually bactericidal. Appears to inhibit protein synthesis in susceptible bacteria by binding to ribosomal RNA and causing misreading of the bacterial genetic code.
Neomycin: Spectrum of activity includes many aerobic gram-negative bacteria and some aerobic gram-positive bacteria. Most streptococci are resistant. Inactive against fungi, viruses, and most anaerobic bacteria.
Neomycin in fixed combination with polymyxin B: Active against Staphylococcus aureus, Escherichia coli, Haemophilus influenzae, Enterobacter, Klebsiella, Neisseria, and Pseudomonas aeruginosa. Does not provide coverage against streptococci (including Streptococcus pneumoniae) or Serratia marcescens.
Neomycin in fixed combination with polymyxin B and bacitracin: Active against S. aureus, streptococci (including S. pneumoniae), E. coli, H. influenzae, Enterobacter, Klebsiella, Neisseria, and Ps. aeruginosa. Does not provide coverage against S. marcescens.
Neomycin in fixed combination with polymyxin B and gramicidin: Active against S. pneumoniae, E. coli, H. influenzae, Enterobacter, Klebsiella, Neisseria, and Ps. aeruginosa. Does not provide coverage against S. marcescens.
Neomycin in fixed combination with colistin: Active in vitro and in superficial infections of the external auditory canal caused by S. aureus, E. aerogenes, E. coli, K. pneumoniae, and Ps. aeruginosa.
Bacteria resistant to neomycin may emerge in patients receiving topical preparations containing the drug.
There is partial cross-resistance between neomycin and other aminoglycosides.

Advice to Patients

Advise patients to avoid contaminating container tip with material from eye, eyelid, ears, fingers, or other source and to not share ophthalmic or otic preparations with others.
Inform patients that serious eye damage and subsequent vision loss may occur if ophthalmic preparations are handled improperly and become contaminated by common bacteria known to cause ocular infections.
Inform patients that their vision may be temporarily blurred after administration of topical ophthalmic preparations; take care in operating machinery or driving a motor vehicle.
Advise patients to immediately discontinue therapy and contact a clinician if signs of sensitivity or allergic reaction occur (rash, pruritus, swelling, redness) or if the condition worsens or does not improve.
Advise patients using fixed-combination ophthalmic preparations containing a corticosteroid to discontinue the drug and contact a clinician if inflammation or pain persists for >48 hours or becomes aggravated.
Importance of patients informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses .
Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.
Importance of informing patients of other important precautionary information. (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Colistin and Neomycin Sulfates and Hydrocortisone Acetate
Routes	Dosage Forms	Strengths	Brand Names	Manufacturer
Otic	Suspension	Colistin Sulfate 3 mg (of colistin) per mL, Neomycin Sulfate 3.3 mg (of neomycin) per mL, and Hydrocortisone Acetate 1%	Coly-Mycin S Otic with Neomycin and Hydrocortisone	Endo
			Cortisporin-TC Otic Suspension	Par