Drug information of Neomycin

Neomycin

Drug group: Aminoglycosides

A component of neomycin that is produced by Streptomyces fradiae. Neomycin is a bactericidal aminoglycoside antibiotic that binds to the 30S ribosome of susceptible organisms. Binding interferes with mRNA binding and acceptor tRNA sites and results in the production of non-functional or toxic peptides.

Mechanism of effect

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.

Pharmacodynamic

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.

Dosage

  • Adult:

Hepatic Encephalopathy

Acute: 4-12 g/day PO divided q6hr for 5-6 days OR 3-6 g/day for 1-2 weeks

Chronic: Up to 4 g/day PO

Hepatic Coma

4 to 12 g/day orally divided every 4 to 6 hours for 5 to 6 days

Diarrhea Caused by Enteropathogenic E.coli

3 g/day PO divided q6hr

Bowel Preparation

1 g orally every hour for 4 doses followed by 1 g every 4 hours for 5 doses

Alternate dosing: 6 g/day orally divided every 4 hours for 2 to 3 days

Steroid Responsive Dermatoses with Infection

Apply cream/ointment BID-QID x up to 7d

  • Pediatric

The safety and efficacy of neomycin in children less than 18 years of age has not been established. However, the use of neomycin may be appropriate is some situations.

Hepatic Encephalopathy and Hepatic Coma

1 month to 18 years: 50 to 100 mg/kg/day orally divided every 6 to 8 hours for 5 to 6 days

Diarrhea

Less than 1 month: 50 mg/kg/day orally divided every 6 hours
1 year to 18 years: 50 mg/kg/day orally divided every 6 hours for 2 to 3 days

Bowel Preparation

Less than 1 month: 50 mg/kg/day orally divided every 6 hours
1 year to 18 years: 50 to 100 mg/kg/day orally divided every 6 hours

Alerts

  • You should not take neomycin if you have ulcerative colitis, Crohn's disease, a blockage in your intestines, or other inflammatory bowel disease.
  • Before you take neomycin, tell your doctor if you have kidney disease, myasthenia gravis, or Parkinson's disease.
  • Neurotoxicity, manifested as both bilateral auditory and vestibular ototoxicity, can occur in patients with preexisting renal damage and in patients with normal renal function treated at higher doses and/or for periods longer than those recommended. High-frequency deafness usually occurs first and can be detected only by audiometric testing
  • Aminoglycosides are potentially nephrotoxic. Risk is greater in patients with impaired renal function and in those who receive high doses or prolonged therapy. Rarely, nephrotoxicity may not become apparent until the first few days after cessation of therapy
  • Use with caution in premature infants and neonates because of renal immaturity and the resulting prolongation of serum half-life of the drug
  • Neuromuscular blockade and respiratory paralysis have been reported following parenteral injection, topical instillation (as in orthopedic and abdominal irrigation or in local treatment of empyema), and oral use of aminoglycosides, especially when given soon after anesthesia or muscle relaxants. If blockage occurs, calcium salts may reverse these phenomena, but mechanical respiratory assistance may be necessary
  • Avoid concurrent or sequential use of neurotoxic and/or nephrotoxic drugs including other aminoglycosides (eg, amikacin, streptomycin, neomycin, kanamycin, gentamicin, paromomycin)
  • Cumulative listing of drugs to avoid from all aminoglycoside package inserts includes amphotericin B, bacitracin, cephaloridine, cisplatin, colistin, polymixin B, vancomycin, and viomycin.
  • Avoid potent diuretics (eg, ethacrynic acid, furosemide) because they increase risk of ototoxicity. When administered intravenously, diuretics may enhance aminoglycoside toxicity by altering antibiotic concentrations in serum and tissue

Points of recommendation

  • Have blood work checked as you have been told by the doctor.
  • Do not use longer than you have been told. A second infection may happen.
  • If you are 65 or older, use this medicine with care. You could have more side effects.
  • Do not use neomycin if you are pregnant. It could harm the unborn baby.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine (neomycin tablets) while you are pregnant.


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