Adult: As adjunctive therapy: 4-12 g daily in divided doses for 5-7 days. For chronic hepatic insufficiency: 4 g daily for an indefinite period. Child: 50-100 mg/kg daily in divided doses for 5-7 days.
Oral Preoperative intestinal antisepsis
Adult: 1 g hourly for 4 hours, then 4 hourly for 2-3 days before the operation. Alternatively, for patients undergoing colorectal surgery in combination with erythromycin: 1 g given at 1 pm, 2 pm and 11 pm on the day preceding 8 am surgery. Child: 6-12 years 250-500 mg 4 hourly for 2-3 days before the operation; >12 years 1g 4 hourly for 2-3 days before the operation.
Special Patient Group
Pharmacogenomics:
Aminoglycosides are broad-spectrum bactericidal antibiotics with narrow therapeutic indexes. It directly binds to the 16S ribosomal RNA in the 30S subunit of the bacterial ribosome which prematurely terminates protein synthesis. Current studies suggest that there is an increased risk of aminoglycoside-associated ototoxicity in patients with mitochondrial mutations, including patients in which aminoglycoside serum levels are within the recommended range.
The primary genetic factor associated with aminoglycoside-associated ototoxicity is the m.1555A>G mutation. The estimated prevalence of this mutation in the general population is 0.2%. It is also found in families with maternally transmitted deafness.
Genetic testing should be considered especially before the initiation of recurrent or long-term treatment but should not delay urgently needed aminoglycoside therapy.
Additionally, studies show that patients with 1555G allele may have a greater risk of aminoglycoside-induced hearing loss compared to patients with 1555A allele, although other genetic and clinical factors may increase this risk.
Renal Impairment
Dosage adjustment may be needed.
Administration
May be taken with or without food.
Contraindications
Hypersensitivity to neomycin or other aminoglycosides. Intestinal obstruction, inflammatory or ulcerative gastrointestinal disease, myasthenia gravis. Infants <1 year.
Special Precautions
Patient with neuromuscular disorders, Parkinson’s disease; hearing impairment; pre-existing vertigo, tinnitus, or hearing loss. Patient with m.1555A>G mitochondrial mutation. Renal and hepatic impairment. Pregnancy and lactation.
Adverse Reactions
Significant: Neurotoxicity; malabsorption with steatorrhoea and diarrhoea, ototoxicity, superinfection (prolonged use). Blood and lymphatic system disorders: Haemolytic anaemia, eosinophilia, Gastrointestinal disorders: Nausea, vomiting, diarrhoea, stomatitis, rectal irritation, anorectal pain. Immune system disorders: Hypersensitivity reactions. Investigations: Increased hepatic enzymes and blood bilirubin. Metabolism and nutrition disorders: Electrolyte imbalance. Nervous system disorders: Paraesthesia, confusion, disorientation, nystagmus. Potentially Fatal: Nephrotoxicity, respiratory depression, neuromuscular blockade.
Monitor serum creatinine/BUN at baseline and periodically during chronic therapy; audiometry in symptomatic patients. Asses for ototoxicity, nephrotoxicity, and neurotoxicity.
Drug Interactions
Increased risk of nephrotoxicity with amphotericin B, ciclosporin, capreomycin, vancomycin, teicoplanin, and platinum compounds. Increased risk of ototoxicity with loop diuretics. May impair the absorption of methotrexate, digoxin, phenoxymethylpenicillin and some vitamins. May enhance the therapeutic effect of muscle relaxants. Increased risk of neuromuscular side-effects with general anaesthetics or opioids. May antagonise the effects of neostigmine and pyridostigmine. May increase the hypoglycaemic effect and severity of gastrointestinal side-effects of acarbose. Increased risk of hypocalcaemia with bisphosphonates. May diminish the therapeutic efficacy of oral contraceptives.
Action
Description: Mechanism of Action: Neomycin is an aminoglycoside antibiotic. It binds to the 30S ribosomal units of susceptible bacteria, thereby causing an inhibition of protein synthesis and consequently errors in the transcription of genetic codes. Pharmacokinetics: Absorption: Poorly absorbed from the gastrointestinal tract. Increased absorption with damaged or inflamed mucosa. Time to peak plasma concentration: 1-4 hours. Distribution: Crosses the placenta. Distributes to tissues and concentrates in the renal cortex. Plasma protein binding: 0-30%. Excretion: Via faeces (97% as unchanged drug); urine (30-50% as unchanged drug). Elimination half-life: 2-3 hours.
J01GB05 - neomycin ; Belongs to the class of other aminoglycosides. Used in the systemic treatment of infections. A07AA01 - neomycin ; Belongs to the class of antibiotics. Used in the treatment of intestinal infections.
References
Gao Z, Chen Y, Guan MX. Mitochondrial DNA Mutations Associated with Aminoglycoside-Induced Ototoxicity. Journal of Otology. 2017;12(1):1-8. doi: 10.1016/j.joto.2017.02.001. Accessed 02/02/2021Mary O'Sullivan, Paul Rutland, Deirdre Lucas, Emma Ashton, Sebastian Hendricks, Shamima Rahman, Maria Bitner-Glindzicz. Mitochondrial m.1584A 12S m62A rRNA Methylation in Families with m.1555A>G Associated Hearing Loss. Oxford Academic. 24(4):1036-1044. doi: 10.1093/hmg/ddu518. Accessed 02/02/2021Tian Nguyen, Anita Jeyakumar. Genetic Susceptibility to Aminoglycoside Ototoxicity. International Journal of Pediatric Otorhinolaryngology. 2019 Feb;120(1):15-19. doi: 10.1016/j.ijporl.2019.02.002. Accessed 02/02/2021. PMID: 30743189Aminoglycosides (Gentamicin, Amikacin, Tobramycin, and Neomycin): Increased Risk of Deafness in Patients with Mitochondrial Mutations. Medicines & Healthcare products Regulatory Agency. https://www.gov.uk/government/organisations/medicines-and-healthcare-products-regulatory-agency. Accessed 02/02/2021.Anon. Neomycin (Systemic). AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 02/02/2021.Anon. Neomycin. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 02/02/2021.Buckingham R (ed). Neomycin. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 02/02/2021.Clinical Annotation for rs267606617 (MT-RNR1); Amikacin, Aminoglycoside Antibacterials, Gentamicin, Kanamycin, Neomycin, Streptomycin or Tobramycin; Ototoxicity. Pharmacogenomics Knowledgebase (PharmGKB). https://www.pharmgkb.org. Accessed 02/02/2021.Joint Formulary Committee. Neomycin Sulfate. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 02/02/2021.Neomycin Sulfate Tablet (Teva Pharmaceuticals USA, Inc.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed. Accessed 02/02/2021.Nivemycin Tablets 500mg (Amidpharm UK Limited). MHRA. https://products.mhra.gov.uk. Accessed 02/02/2021.