More Related Content
Muztaba
- 1. PRESENTATION ON: AMINOGLYCOSIDE INTEGRAL UNIVERSITY,LUCKNOW Session: 2016-2017 Presented by: Under the guidence of: Mohd Muztaba Dr .Anuradha Mishra M.Pharm 1st year Pharmacology
- 2. These are a group of natural and semisynthetic antibiotics having polybasic amino groups linked glycosidically to two or more aminosugar (strephdine2-deoxy streptamine garosamine) residue. Unlike penicilline which was a chance discovery aminoglycosides are products of deliberate search for drugs effective against gram-negative bacteria. All aminoglycosides are produced by soil actinomycetes
- 3. CLASSIFICATION Systemic aminoglycosides Streptomycine, Amikacin Gentamicin, Sisomicin Kanamycin Topical aminoglycosides Neomycin , Framycetin
- 4. MECHANISM OF ACTION The aminoglycosides are bactericidal antibiotic Transport of the aminoglycosides through bacterial cell wall & cytoplasmic membrane (diffusion-outer coat-Gm –ve via porin channel) Irreversibly Binding to ribosomes (mostly 30s and 50s,30s &50s interface) resulting in inhibition of protein synthesis.
- 6. MECHANISM OF RESISTANCE Production of a transferase enzyme or enzymes inactivates the aminoglycoside by acetylation, or phosphorylation. This is the principal type of resistance encountered clinically There is impaired entry of aminoglycoside into the cell. This may be genotypic, resulting from mutation or deletion of a proteins involved in transport and maintenance of the electrochemical gradient; or phenotypic, eg, resulting from growth conditions under which the oxygen-dependent transport process described above is not functional The receptor protein on the 30S ribosomal subunit may be deleted or altered as a result of a mutation.
- 7. CONTRAINDICATIONS : hypersensitivity to aminoglycosides or bisulfites DRUG INTERACTION : • Inactivated by penicillins and cephalosporins when coadministered to pateints with renal insufficiency. • Increased incidence of ototoxicity with loop diuretics. • Increased incidence of nephrotoxicity with other nephrotoxic drugs. SIDE EFFECTS : nausea,vomiting,urticaria,muscles weakness,rash etc. ADVERSE EFFECTS: vertigo,myocarditis,thrombocytopenia, leukemia,hepatic necrosis,muscle paralysis, etc. TOXICITY : ototoxicity,nephrotoxicity
- 8. STREPTOMYCIN • It is older antibiotics and obtained by Streptomyces griseus, used in past but now used for treatment of TB M.O.A • Inhibit initiation of translation by binding to 16s rRNA. MECHANISM OF RESISTANCE • Mutations in (16sRNA) or (ribosomal protein) which produce alterations in the streptomycin binding site Cross resistance: • Partial or unidirectional cross resistance occur.
- 9. Pharmacokinetics • Neither absorbed nor destroyed in git. • Absorption from injection site in muscle is rapid. • Distributed extracellularly, volume of distribution 0.3 L/kg • It is not metabolized. Excreted unchanged in urine • Plasma half life is 2-4 hrs Adverse effects • Vestibular disturbances, auditory disturbances • Nephrotoxicity • Hypersensitivity are rare-rashes, eosinophilia, dermatitis • Pain at injection site
- 10. CONTRAINDICATION: pregnancy causes foetal ototoxicity DOSE: Tb – 1g or 0.75 g i.m OD or thrice weekly for 30-60 days Acute infection: 1g i.m OD or BD for 7-10 days USES: TB, given with pencillin/ampicillin/vancomycin for 4-6 weeks • Plague: rapid cure within 7-12 days • Tularemia: Streptomycin cures it in 7-10 days
- 11. GENTAMYCIN Gentamicin is an aminoglycoside isolated from Micromonospora purpurea . It is effective against both gram- positive and gram-negative organisms Antimicrobial Activity Gentamicin sulfate inhibits in vitro many strains of staphylococci and coliforms and other gram-negative bacteria.
- 12. RESISTANCE gentamicin in combination with vancomycin or a penicilline produces a potent bactericidal effect, which in part is due to enhanced uptake of drug that occurs with inhibition of cell wall synthesis Resistance to gentamicin rapidly emerges in staphylococci during monotherapy owing to selection of permeability mutants. Ribosomal resistance is rare. Among gram-negative bacteria, resistance is most commonly due to plasmid-encoded aminoglycoside-modifying enzyme Gram-negative bacteria that are gentamicin-resistant usually are susceptible to amikacin, which is much more resistant to modifying enzyme activity.
- 13. AMIKACIN It is a semisynthetic aminoglycoside It is effective against several gram negative organism including Escherichia coli Mycobacterium tuberculosis It is bactericidal effect Amikacin in highly effective against pseudomonas RESISTANCE decreased uptake and/or accumulation of the drug in bacteria the bacterial expression of enzymes which modify the antibiotic and thereby inactivate it
- 14. ADVERSE EFFECT • Vertigo • Ataxia • Ototoxicity • Nephrotoxicity USE • Rt i • Bone and joint infection • Skin and soft tissue infection
- 15. INTRACTION Amphoterecin b may leads to increase nephrotoxicity and reduce the clearance of amikacin when use in together Increse risk of ototoxicity with potent diuretics
- 16. NEOMYCIN & KANAMYCIN wide spectrum active against Gm-ve bacilli and some gm+ve cocci and obtained from Streptomyces.fradiae Antimicrobial Activity & Resistance Drugs of the neomycin group are active against gram-positive and gram-negative bacteria and some mycobacteria.and streptococci are generally resistant. Mechanisms of antibacterial action and resistance are the same as with other aminoglycosides. The widespread use of these drugs in bowel preparation for elective surgery has resulted in the selection of resistant organisms and some outbreaks of enterocolitis in hospitals. Cross-resistance between kanamycin and neomycin is complete.
- 17. USES:Topically used in skin, eye and external ear infections combined with bacitracin or polymyxin-B to widen antibacterial spectrum and to prevent emergence of resistant strains Orally Preparation of bowel before surgery 1 gm TDS ADVERSE EFFECT Applied topically neomycin has low sensitizing potential However, rashes do occur. Oral neomycin has a damaging effect on intestinal villi- prolonged treatment can induce malabsorption syndrome with diarrhoea It can decrease the absorption of digoxin and many other drugs, as well as bile acids.
- 18. FARAMYCETIN it is very similar to neomycin. It is too toxic for systemic administration and is used topically on skin, eye, ear in the same manner as neomycin.
- 19. THANK YOU