Brands, Medical Use, Clinical Data
- Anti-bacterial Agents
Brands / Synonyms
Biosol; Bykomycin; Caswell No. 595; Cortisporin; Cortisporin-TC; Endomixin; Fradiomycin; Fradiomycin Sulfate; Fraquinol; Lidamycin Creme; Maxitrol; Myacine; Myacyne; Mycifradin; Mycifradin-N; Myciguent; NEO-Fradin; Neo-Mantle Creme; Neo-Rx; Neobiotic; Neobrettin; Neofracin; Neolate; Neomix; Neomycin; Neomycin and Polymyxin B Sulfates; Neomycin and Polymyxin B Sulfates and Bacitracin Zinc; Neomycin and Polymyxin B Sulfates and Bacitracin Zinc with Hydrocortisone; Neomycin and Polymyxin B Sulfates and Dexamethasone; Neomycin and Polymyxin B Sulfates and Gramicidin Ophthalmic; Neomycin and Polymyxin B Sulfates and Hydrocortisone; Neomycin B Sulfate; Neomycin Sulfate; Neomycin Sulphate; Neomycin Sulphate Puriss for Bacteriology; Neomycin trisulfate salt hydrate; Neosporin; Neosporin GU; Neosulf; Nivemycin; Poly-Pred; Statrol; Tuttomycin; USAF CB-19; Vonamycin Powder V
For the adjunctive treatment of acute hepatic failure, alcoholic cirrhosis of the liver, and suppression of intestinal bacteria.
Neomycin is an aminoglycoside antibiotic. Aminoglycosides work by binding to the bacterial 30S ribosomal subunit, causing misreading of t-RNA, leaving the bacterium unable to synthesize proteins vital to its growth. Aminoglycosides are useful primarily in infections involving aerobic, Gram-negative bacteria, such as Pseudomonas, Acinetobacter, and Enterobacter. In addition, some mycobacteria, including the bacteria that cause tuberculosis, are susceptible to aminoglycosides. Infections caused by Gram-positive bacteria can also be treated with aminoglycosides, but other types of antibiotics are more potent and less damaging to the host. In the past the aminoglycosides have been used in conjunction with penicillin-related antibiotics in streptococcal infections for their synergistic effects, particularly in endocarditis. Aminoglycosides are mostly ineffective against anaerobic bacteria, fungi and viruses.
Mechanism of Action
Aminoglycosides like neomycin "irreversibly" bind to specific 30S-subunit proteins and 16S rRNA. Specifically neomycin binds to four nucleotides of 16S rRNA and a single amino acid of protein S12. This interferes with decoding site in the vicinity of nucleotide 1400 in 16S rRNA of 30S subunit. This region interacts with the wobble base in the anticodon of tRNA. This leads to interference with the initiation complex, misreading of mRNA so incorrect amino acids are inserted into the polypeptide leading to nonfunctional or toxic peptides and the breakup of polysomes into nonfunctional monosomes.
Poorly absorbed from the normal gastrointestinal tract. Although only approximately 3% of neomycin is absorbed through intact intestinal mucosa, significant amounts may be absorbed through ulcerated or denuded mucosa or if inflammation is present.
LD50 = 200 mg/kg (rat). Because of low absorption, it is unlikely that acute overdosage would occur with oral neomycin. However, prolonged administration could result in sufficient systemic drug levels to produce neurotoxicity, ototoxicity and/or nephrotoxicity.
Biotrnasformation / Drug Metabolism
Neomycin undergoes negligible biotransformation after parenteral administration.
Neomycin sulfate oral preparations are contraindicated in the presence of intestinal obstruction and in
individuals with a history of hypersensitivity to the drug.
Patients with a history of hypersensitivity or serious toxic reaction to other aminoglycosides may have a
cross-sensitivity to neomycin.
Neomycin sulfate oral preparations are contraindicated in patients with inflammatory or ulcerative
gastrointestinal disease because of the potential for enhanced gastrointestinal absorption of neomycin.
Caution should be taken in concurrent or serial use of other neurotoxic and/ or nephrotoxic drugs because of
possible enhancement of the nephrotoxicity and/or ototoxicity of neomycin.
Caution should also be taken in concurrent or serial use of other aminoglycosides and polymyxins because they may
enhance neomycinís nephrotoxicity and/or ototoxicity and potentiate neomycin sulfateís neuromuscular
Oral neomycin inhibits the gastrointestinal absorption of penicillin V, oral vitamin B-12, methotrexate and
5-fluorouracil. The gastrointestinal absorption of digoxin also appears to be inhibited. Therefore, digoxin serum
levels should be monitored.
Oral neomycin sulfate may enhance the effect of coumarin in anticoagulants by decreasing vitamin K