Pharmacotherapy of antibiotic Tetracycline.ppt

Tetracycline is a short-acting antibiotic that inhibits bacterial growth by inhibiting translation. It binds to the 30S ribosomal subunit and prevents the amino-acyl tRNA from binding to the A site of the ribosome. It also binds to some extent to the 50S ribosomal subunit. This binding is reversible in nature. Semi-synthetic tetracyclines are lymecycline, methacycline, minocycline, rolitetracycline, and doxycycline. There is one glycylcycline subclass agent named tigecycline.

1. Tetracycline

2. Drugs available: Tetracycline Oxytetracycline Demeclocycline Doxycycline Minocycle Glyclycycline: Tigecycline

3. Mechanism of action Actively taken up by the susceptible bacteria Binds reversibly to 30s ribosomal subunit Prevent binding of aminoacyl t-RNA to m-RNA ribosomal complex Prevent addition of amino acid to the growing peptide chain Inhibit bacterial protein synthesis (Bacteriostatic action)

4. Resistance: EFFLUX: Reduced cytoplasmic concentration Ribosomal binding site protection by plasmid mediated synthesis of protein Alteration of target : MUTATION in 16 s-RNA

5. Gram positive and gram negative cocci Enterococci Strep pyogenes Stap h aureus N.Meningitidis

6. Gram positive bacilli Clostridia Listeria Propionibacterium acne Gram negative bacilli V.Cholera Campylobacter H.Ducreyi Yersinia pestis

7. Spirochetes T Pallidum Borrelia Protozoa Rickettsiae (Typhus) Chlamydiae Mycoplasma Actinomyces Entamoeba H istolytica

8. Uses Empirical therapy Mixed infections Combination of Beta lactams with Aminoglycoside 3 rd Generation cephalosporins Fluoroquinolone 1 st Choice Venereal disease: Chlamydial nonspecific urethritis Lymphogranuloma venerum Granuloma inguinale Atypical pneumonia Cholera Brucellosis Plague Relapsing fever Rickettsial infections Other situations UTI CAP Amoebiasis Acne vulgaris As adjuvant to quinine or artesunate for chloroquine resistant Falciparum

9. Uses 2 nd Choice To penicillin/Ampicillin Tetanus, anthrax, actinomycosis, listeria To Ceftriaxone, amoxicillin, azithromycin in patients allergic to penicillin Gonorrhea To Ceftriaxone in patients allergic to penicillin Syphilis To P enicillin Leptospirosis To Azithromycin due to chlamydia pneumoniae Pneumonia To Ceftriaxone / A zithromycin Chancroid

10. Adverse effects K: Kidne y damage (Except-Doxycycline) A: Anti anabolic effects ( Protein synthesis) ( Blood urea) P: Phototoxicity (Max with Demeclocycline/Doxy) I: Insipidus (Diabetes) (Demeclocycline) L: Liver disease (Except- Tetracycline) D : Dentition (Brown discoloration) E: Epigastric pain, Nausea, Vomiting, Diarrhea V: Vestibular toxicity (Minocycline) S: Superinfections

11. Pregnancy, Lactation, children Increase in blood urea Renal and hepatic insufficiency Do not inject intramuscular Precautions

12. Tigecycline Resistance mechanism like efflux pump, Protecting the ribosomal binding site do not operate against tigecycline Gram positive and gram negative cocci Gram positive and negative bacilli Anaerobes Tetracycline resistant strains of strep pyogenes, strep pneumoniae, MRSA, VRSA, VRE, Enterobacteriaceae, New class of synthetic tetracycline analogues (Glyclycycline) Route of administration: Slow IV infusion Duration of action: Long

13. Use: Serious and hospitalized patients of CAP, Complicated and skin structure infections, complicated intraabdominal infections caused by enterococci, anaerobes and Enterobacteriaceae. C/I: Pregnancy, Lactation, children ADVERSE EFFECTS: Epigastric pain, Nausea, Vomiting, Diarrhea Phototoxicity (Max with Demeclocycline/Doxy) Superinfections