Polymyxin B + Neomycin Ear prep

Indications

Polymyxin B + Neomycin Ear prep is used for: Otitis externa

Adult Dose

Otic/Aural Otitis externa Adult: Instill 3 drops into affected ear(s) 3-4 times daily. Alternatively, insert a gauze wick into the canal and keep it saturated with the solution for 24-48 hours. Discontinue if there is no clinical improvement after 7 days.

Child Dose

Otic/Aural Otitis externa Child: >3 years Instill 3 drops into affected ear(s) 3-4 times daily. Alternatively, insert a gauze wick into the canal and keep it saturated with the solution for 24-48 hours. Discontinue if there is no clinical improvement after 7 days.

Renal Dose

Renal impairment: Dosage reduction may be necessary.

Administration

Contra Indications

Hypersensitivity to polymyxin B, neomycin and hydrocortisone and other aminoglycosides. Perforated tympanic membrane, untreated viral, fungal and tubercular infections. Children <3 years.

Precautions

Patient with conditions where significant systemic absorption may occur, venous stasis eczema and ulceration, pre- and post-operative period. Prolonged use. Children. Pregnancy and lactation.

Pregnancy-Lactation

Interactions

Neomycin and polymyxin may increase risk of respiratory depression with neuromuscular blocking agents.

Adverse Effects

Side effects of Polymyxin B + Neomycin Ear prep : Significant: Irreversible ototoxicity (e.g. deafness), nephrotoxicity, neurotoxicity, neomycin sensitisation (e.g. itching, reddening, oedema, failure to heal), immunosuppression, Kaposi sarcoma, and suppression of the pituitary-adrenal (HPA) axis after systemic absorption. Ear and labyrinth disorders: Stinging, burning sensation in ears. Potentially Fatal: Pseudomembranous colitis.

Mechanism of Action

Polymyxin B is a bactericidal active against a wide range of gram negative bacilli. It binds to acid phospholipids in the bacterial cytoplasmic membrane, thereby altering permeability and disrupting the osmotic barrier leading to cell death. Neomycin, an aminoglycoside, is a bactericidal active against a wide range of gram positive and gram negative bacteria. It interferes with bacterial protein synthesis by binding to 30S ribosomal subunits