Bacitracin Zinc + Neomycin Sulphate + Polymixin B Eye prep
Indications
Bacitracin Zinc + Neomycin Sulphate + Polymixin B Eye prep is used for:
Bacterial ocular infections
Adult Dose
Adult: Eye Drop: 1-2 drops 3-4 times daily.
Eye ointment: Apply 1/2 inch ribbon of ointment to conjunctival sac of affected eye(s) q3-4hr for 7-10 days for acute infections
Child Dose
Child: Eye Drop: 1-2 drops 3-4 times daily.
Eye ointment: Apply 1/2 inch ribbon of ointment to conjunctival sac of affected eye(s) q3-4hr for 7-10 days for acute infections
Renal Dose
Administration
Contra Indications
Hypersensitivity
Precautions
Excessive use of the topical preparation may lead to substantial systemic absorption which may lead to nephrotoxicity (polymyxin B sulfate) and neurotoxicity (bacitracin). Prolonged use of the antibacterial preparation may cause overgrowth of non-susceptible organisms, including fungi. Pregnancy and lactation.
Lacation: Excretion in breast milk unknown; caution
Pregnancy-Lactation
Pregnancy Category: C
Lacation: Excretion in breast milk unknown; caution
Interactions
Bacitracin Zinc: Increased risk of nephrotoxicity when used with other nephrotoxic drugs. May enhance the action of neuromuscular-blocking agents.
Neomycin Sulphate: Additive nephrotoxic and neurotoxic effect w/ other aminoglycosides (e.g. paromomycin), bacitracin, cisplatin, vancomycin, amphotericin B, polymyxin B, colistin and viomycin. Enhanced toxicity w/ potent diuretics (e.g. ethacrynic acid, furosemide). May impair the absorption of other drugs (e.g. phenoxymethylpenicillin, digoxin, methotrexate and some vit). May reduce the efficacy of OCs. May enhance the effect of acarbose. May enhance the effect of non-depolarising muscle relaxants. May antagonise the parasympathomimetic effect of neostigmine and pyridostigmine. May increase the risk of hypocalcaemia in patients receiving bisphosphonates. May alter INR when given w/ anticoagulants. May inactivate oral typhoid vaccine.
Polymixin B: Potentially Fatal: Additive neurotoxic or nephrotoxic effect w/ bacitracin, streptomycin, neomycin, kanamycin, gentamicin, tobramycin, amikacin, cephaloridine, paromomycin, viomycin, colistin. Increased risk of resp paralysis w/ neuromuscular blockers (e.g. anaesthetics, muscle relaxants).
Side Effects
Side effects of Bacitracin Zinc + Neomycin Sulphate + Polymixin B Eye prep :
Rash, itching, burning, anaphylactic reactions, swelling, conjunctival erythema.
Mode of Action
Neomycin, an aminoglyoside with antimicrobial spectrum similar to gentamicin, binds to the 30S subunits of the bacterial ribosome, inhibiting protein synthesis and thereby disrupting DNA synthesis. It is active against many gram-negative aerobes and against some strains of staphylococci.
Bacitracin, on the other hand, inhibits bacterial cell wall synthesis and is active against many gram-positive bacteria (e.g. staphylococci, streptococci, corynebacteria and clostridia) and some gram-negative species (e.g. Neisseria and Haemophilus influenzae). They are often found in combinations in topical preparations as broad spectrum antibacterial agents.
Polymyxin B disrupts the bacterial cytoplasmic membrane of mostly gm-ve organisms allowing leakage of intracellular constituents by binding to membrane phospholipids.