Product Information
Registration Status: ActiveOFTALMOLOSA CUSI GENTAMICIN EYE OINTMENT 0.3% is approved to be sold in Singapore with effective from 1995-02-02. It is marketed by NOVARTIS (SINGAPORE) PTE LTD, with the registration number of SIN07995P.
This product contains Gentamicin 3mg in the form of OINTMENT. It is approved for OPHTHALMIC use.
This product is manufactured by ALCON CUSI SA in SPAIN.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Description
A complex of three different closely related aminoglycoside sulfates, Gentamicins C1, C2, and C1a, obtained from Micromonospora purpurea and related species. They are broad-spectrum antibiotics, but may cause ear and kidney damage. They act to inhibit protein synthesis (genetic translation).
Indication
For treatment of serious infections caused by susceptible strains of the following microorganisms: P. aeruginosa, Proteus species (indole-positive and indole-negative), E. coli, Klebsiella-Enterobactor-Serratia species, Citrobacter species and Staphylococcus species (coagulase-positive and coagulase-negative).
Mechanism of Action
Aminoglycosides like gentamicin "irreversibly" bind to specific 30S-subunit proteins and 16S rRNA. Specifically gentamicin 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.
Pharmacokinetics
- Absorption
- Injections lead to peak serum concentrations in 30-60 minutes. Topical gentamicin is readily absorbed from large burned, denuded, or granulating areas but not through intact skin. Absorption of gentamicin is faster and greater with the cream compared to the ointment. Gentamicin is absorbed in small quantities following topical application to the eye. Gentamicin is also absorbed in small amounts following topical application to the ear (especially if the eardrum is perforated or if tissue damage is present). Gentamicin is very poorly absorbed orally.
- Distribution
- Metabolism
- Elimination
Toxicity
Mild and reversible nephrotoxicity may be observed in 5 - 25% of patients. Gentamicin accumulates in proximal renal tubular cells and causes cell damage. Tubular cell regeneration occurs despite continued drug exposure. Toxicity usually occurs several days following initiation of therapy. May cause irreversible ototoxicity. Otoxocity appears to be correlated to cumulative lifetime exposure. Drug accumulation in the endolymph and perilymph of the inner ear causes irreversible damage to hair cells of the cochlea or summit of ampullar cristae in the vestibular complex. High frequency hearing is lost first with progression leading to loss of low frequency hearing. Further toxicity may lead to retrograde degeneration of the 8th cranial (vestibulocochlear) nerve. Vestibular toxicity may cause vertigo, nausea, vomiting, dizziness and loss of balance. Mouse, intravenous LD50: 52 mg/kg; rat, intravenous LD50: 96 mg/kg.
Active Ingredient/Synonyms
Gentamicin | Gentamicin |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.