Gentamicin Drug - Medicinal Chemistry & Uses

By: Pharma Tips | Views: 7252 | Date: 25-Oct-2011

Gentamicin belongs to the class of antibiotics called Aminoglycosides. Most of the Aminoglycosides are isolated from Streptomyces or micromonospora sp. Aminoglycosides are highly water soluble due to their polar groups (hydroxyl and amine groups) and are very well distributed through the body fluids.

Introduction to aminoglycosides:

Gentamicin belongs to the class of antibiotics called Aminoglycosides.  Most of the Aminoglycosides are isolated from Streptomyces or micromonospora sp.  Aminoglycosides are highly water soluble due to their polar groups (hydroxyl and amine groups) and are very well distributed through the body fluids.  They are very poorly distributed to the bones, CNS, and fatty tissues due to their polar groups and have very poor oral absorption.  They have a broad spectrum of action against both gram positive and gram negative bacteria, but are better against gram negative bacteria due to their polar groups which allow them to cross into the bacterial cell well through porins.

Gentamicin

Mechanism of action:

The aminoglycosides are bactericidal. They act by binding essentially irreversibly to the 30S ribosomal subunit and inhibiting protein synthesis. There are two main ways that they can do this. First, they interfere with amino acid polymerization and elongation, which essentially halts protein biosynthesis. Second, they cause tRNA to misread amino acid codons, and they also impair proofreading mechanisms. This leads to the incorporation of incorrect amino acids into the protein chain, leading to faulty, inactive proteins. It appears that one of these mechanisms is more important than the other in some aminoglycosides. However, it is possible that the determination of which mechanism takes place is based on the concentration of the aminoglycoside inside the cell. It is postulated that the second mechanism occurs rapidly at low aminoglycoside concentrations, and the first mechanism provides the more extended antibacterial effects of this drug class.

 
Resistance:

Bacteria can become resistant to gentamicin through the production of inactivating enzymes. These enzymes cause N-acetylation of the amine groups on the gentamicin structure as well as phosphorylation and adenylation of the hydroxyl groups. Because gentamicin is missing some of the groups that can be acted upon by these enzymes, resistance is not as much of a problem as with some of the other aminoglycosides. Other mechanisms of resistance include mutations of the ribosome and decreased uptake of the drug into the bacterial cell.

Important Dispensing Information for Gentamicin:

Clinical Use of Gentamicin:

Gentamicin is FDA approved for the treatment of serious gram negative bacterial infections and for the treatment of peritoneal dialysis-associated peritonitis. It is often used to treat gram negative nosocomial infections that are resistant to other antibiotics.

Dose and Dosage Forms:

Gentamicin is available for intravenous, topical, or opthalmic administration. Gentamicin is available for injection as 2 mg/ml, 10 mg/ml, or 40 mg/ml solutions. Topically, gentamicin is available as a 0.1% cream or an 0.1% ointment. Gentamicin is also available for opthalmic application as an 3 mg/ml ointment or a 3 mg/ml solution. Gentamicin is renally eliminated and dosage adjustments are required for patients with renal impairment. It is not necessary to adjust the dose in patients with hepatic failure.

Adverse Effects:

The most common adverse effects reported with gentamicin use are nephrotoxicity and ototoxicity. Gentamicin may also cause neuromuscular blockade. Gentamicin should not be taken by patients who are allergic to aminoglycosides.

Drug Interactions:

Many drugs may increase the potential for adverse effects with Gentamicin. Medicines that affect the kidneys, such as other aminoglycosides, may increase the risk of kidney damage and should be avoided. Bacitracin may also increase the risk of nephrotoxicity. Loop diuretics may increase the risk for ototoxicity and should be avoided. Because Gentamicin causes a neuromuscular blockade, other neuromuscular blocking drugs, such as succinylcholine may have an additive effect and may require dose adjustment.

Gentamicin is pregnancy category D.

Future Uses

According to Foye's Principles of Medicinal Chemistry, gentamicins are decreasing in popularity, since they have "similar clinical spectra to those of the Quinolones."  In the future gentamicin use will continue to decline. The high affinity and long half life of gentamicin in kidney tissue can lead to nephrotoxicity, and ototoxicity and neurotoxicitiy can occur as well. The side effects are so severe that aminoglycoside use is often limited to serious infections caused by gram negative organisms. There have also been reports of bacterial resistance, and even though gentamicin has modifications (missing the hydroxyl group and additional groups on ring 3) to avoid resistance, it is just a matter of time before this is overcome. There are also two lesser mechanisms of resistance involving ribosomal mutations and decreased permeability that may play a more prominent role in the future. Gentamicin will not be an important antibacterial in the future.

Previous Page Next Page

People Searching On This Page:
  • gentamicin injection action
  • gentamicin uses
  • chemistry of gentamicin
  • gentamicin tablet
  • gentamicin tabs
  • gentamicin introduction
  • gentamicin chemical medicine name
  • gentamicin in the form of tablets india
  • tablets of aminoglocoside
  • Chemistry of gentamicin ointment
  • is aminoglycoside available in tab form
  • aminoglycosides uses in india
  • account camarabauru.sp.gov.br loc:IN
  • info itapira.sp.gov.br loc:IN
  • info funed.mg.gov.br loc:IN

Related Pages


B.Pharm/M.Pharm for Drugs Inspector under Directorate of Drugs control

B.Pharm/M.Pharm for Drugs Inspector under Directorate of Drugs control

Jobs | Drug Inspector
Date:
02-Mar-2016  Views: 27742

Online applications are invited from Indian Citizen and such other national as declared eligible by Government of India for recruitment to the 88 post ...
Drug Inspector Jobs Under Food & Drug Administration

Drug Inspector Jobs Under Food & Drug Administration

Jobs | Drug Inspector
Date:
22-Apr-2015  Views: 18443

MPSC invites applications by online method for post of Drug Inspector under Food & Drug Administration, Medical Education and Research Services. For t ...
Career as Drug Inspector at Food & Drug Administration

Career as Drug Inspector at Food & Drug Administration

Jobs | Drug Inspector
Date:
16-Feb-2015  Views: 12842

Online applications are invited from candidates by Food & Drug Administration department Chhattisgarh for given vacancies. ...
Drugs Inspector Job Vacancy  in Drugs Control Department of KPSC

Drugs Inspector Job Vacancy in Drugs Control Department of KPSC

Jobs | Drug Inspector
Date:
05-Jul-2012  Views: 35706

Vacancy for Drugs Inspector in Drugs Control department of KPSC - Freshers may apply ...
Drug Inspector in A.P. Drugs Control Job Vacancy

Drug Inspector in A.P. Drugs Control Job Vacancy

Jobs | Drug Inspector
Date:
18-Feb-2012  Views: 23234

Recruitment applications are invited On-line through the proforma Application to be made available on WEBSITE (apspsc.gov.in) in from 22/02/2012 to 22 ...
Post Your Comments (No Login Require)
Name : (required)
Email : (required)
Website :

Comment : (required)

19  + 3 =     
Comments
People Searched About:
Gentamicin Injection Action   |   Gentamicin Uses   |   Chemistry Of Gentamicin   |   Gentamicin Tablet   |   Gentamicin Tabs   |   Gentamicin Introduction   |   Gentamicin Chemical Medicine Name   |   Gentamicin In The Form Of Tablets India   |   Account Camarabauru.Sp.Gov.Br Loc:IN   |   Info Itapira.Sp.Gov.Br Loc:IN   |   Info Funed.Mg.Gov.Br Loc:IN   |   Info Camarasuzano.Sp.Gov.Br Loc:IN   |   Info Porteirinha.Mg.Gov.Br Loc:IN   |   Info Contabilista-Sp.Com.Br Loc:IN   |  
Google : 1531 times | Yahoo : 20 times | Bing : 341 times |