Aminoglycosidess antibiotics powerpoint presentation

aminoglycosides

1. AMINOGLYCOSIDES

2. All Aminoglycosides are produced by soil actinomycetes Systemic aminoglycosides Streptomycin, Amikacin, Gentamicin, Kanamycin, Netilmicin , Tobramycin Paromomycin Topical aminoglycosides N eomycin and Framycetin

3. Discovered Streptomycin – 1952 – Nobel prize – Waksman

4. CLASSIFICATION A. Neomycin family eg : Neomycin , Paramomycin B. Kanamycin family eg : Kanamycin , Amikacin , Tobramycin C. Gentamicin Family eg : Gentamicin , Netilmicin D. Streptomycin family eg : Streptomycin

5. GENERAL FEATURES OF AMINOGLYCOSIDES None absorbed orally Excreted through kidney unchanged Synergism with beta lactams, Vancomycin Narrow Margin of Safety

6. MECHANISM OF ACTION Irreversible inhibitors of Protein synthesis Primary site of action- 30 S ribosomal subunit

7. Mechanisms of Resistance Failure to penetrate intracellularly Inactivation by microbial enzymes Alteration of target (30 S ribosomal subunit)

8. PHARMACOKINETICS – ABSORPTION Once daily dosing - More effective - Less toxic (safer) - Less costly - Easy Administration - Determination of serum concentration not necessary <3 days

9. EXCEPTIONS TO ONCE DAILY DOSING Pregnancy Neonatal and pediatric infection In combination therapy In renal impairment (creatinine clearance < 25 ml / min)

10. ADVERSE EFFECTS Ototoxicity Nephrotoxicity Neuromuscular Blockade

11. OTOTOXICITY Vestibular Effects Auditory effects Streptomycin Amikacin Gentamicin Kanamycin Neomycin Tobramycin

12. Risk Factors for Nephrotoxicity include : : Prolonged duration of therapy Increased age Preexisting renal insufficiency Concurrent use of other nephrotoxins

13. THERAPEUTIC USES OF AMINOGLYCOSIDES Gram negative bacillary infection Bacterial endocarditis Other infections -Tuberculosis Tularemia Plague Brucellosis 4. Topical uses - Neomycin Framycetin Tobramycin Oral – Paramomycin

14. STREPTOMYCIN Source – S. griseus Dose : 15mg/kg/day when creatinine clearance > 80 ml / min 1000mg single daily dose Therapeutic uses Bacterial endocarditis Tularemia Plague Tuberculosis Brucellosis

15. GENTAMICIN Source : Micromonospora purpurea Most commonly used aminoglycoside Least expensive

16. THERAPEUTIC USES OF GENTAMICIN Complicated urinary tract infections esp. in pyelonephritis Hospital-acquired pneumonia (always in combination with beta-lactam antibiotics) Meningitis– Pseudomonas, Peritoneal dialysis – Associated peritonitis Bacterial endocarditis Sepsis Topical applications

17. TOBRAMYCIN Source – S. tenebrarius Antibacterial spectrum (pseudomonas) Dose : 3-5 mg/kg / day 300 mg in 5ml  for inhalation therapy ( cystic fibrosis) KANAMYCIN Source – S. kanamyceticus Limited spectrum, most toxic (Use almost obsolete)

18. AMIKACIN Semisynthetic derivative of Kanamycin Broadest spectrum among aminoglycosides Uses – Hospital acquired gram negative infections MDR tuberculosis Disseminated atypical mycobacterial infection in AIDS patients NETILMICIN Latest to be marketed Dose 5-7 mg/day . Therapeutically toxicity – Same as gentamicin

19. NEOMYCIN Broad spectrum antibiotic Toxic for systemic use FRAMYCETIN Preparations: 1% skin cream 0.5% eye drops/ointment

20. PAROMOMYCIN orally used aminoglycoside For treatment of Entamoeba histolytica, Cryptosporidiosis and Giardiasis Topical cream for vaginal trichomoniasis (6.25%)