NEWER ANTIBIOTICS - newer antibiotics. newer antibiotics b-lactams quinolones cephalosporins...

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Transcript of NEWER ANTIBIOTICS - newer antibiotics. newer antibiotics b-lactams quinolones cephalosporins...

  • NEWER ANTIBIOTICS

  • NEWER ANTIBIOTICS

    B-LACTAMS QUINOLONES CEPHALOSPORINS LEVOFLOXACIN

    SPARFLOXACIN CEFDITOREN GATIFLOXACIN CEFEPIME GREPOFLOXACIN CEFEPIROME TRAVOFLOXACIN

    CARBAPENEMS MOXIFLOXACIN ERTAPENEM CLINAFLOXACIN

    MACROLIDES OXAZOLIDINONES DIRITHRMYCIN LINEZOLID

    STREPTOGRAMINS JOSAMYCIN DALFOPRISTIN

    AMINOGLYCOSIDES QUINPRISTIN ARBIKACIN GLYCO/LIPOPEPTIDES

    DAPTOMYCIN ORITAVANICIN

    GLYCINCYCLINS TEGICYCLINS

  • CEPHALOSPORINS • The activity of cephalosporins increases over gram negative organisms

    as the generation passes • 4th generation are even resistant to b-lactamases and highely active

    against pseudomonas • They act by inhibiting cell wall synthesis • INDICATION DOSAGE :cefditoren at 200-400mg po12hly indicated

    for bronchitis, complicated sinusitis,otitis media,uti cefepime at 500-2g iv 8-12hly indicated for empirical therapy in febrile neutropenic patients and ABR gram-ve bacteremia

    • ADVERSE EFFECTS:git effects, thrombophlebitis(cfepime), rare ones like hypersensitivity,interstitial nephritis,anemia, leukopenia

    • CONTRAINDICATIONS: Decreased dosage in renal failure .cefepirome contra in pregnancy lactating .cefepime is to used with caution in lactating patients

  • QUINOLONES

    • The activity of quinolones increases over gram +ve organisms as the generation increases .4th generation drugs are active against even anaerobic organisms

    • INDICATIONS: levofloxacin(250-750mg po od)for sinusitis, bronchitis, pneumonia, uti . Gatifloxacin(400mg po/iv od 7-14days) for LRTI,UTI, gonorrhea .moxifloxacin(400mg po/iv od) for sinusitis,bronchitis ,pneumonia

    • ADVERSE EFFECTS :most well tolerated drugs .nasuea ,rashes, cns disturbances .

    • INTERACTIONS: increases QT interval • CONTRAINDICATIONS:2nd,3rd generation decrease dosage in renal

    failure .4th generation decrease dosage in hepatic failure • Not to used in pregnancy lactating children below 18yrs

  • GLYCINCYCLINS(TEGICYCLIN)

    • Bacteriostatic drug having good activity against gram+ve and gram – ve organisms

    • Activity similar to tetracyclins • Inhibits protein synthesis by binding with 30s subunit • INDICATION: complicated skin&intra abdominal infections caused

    by susceptable strains • DOSAGE:100mg stat followed by 50mg every 12th hly IV for 5-14days • ADVERSE EFFECTS: git side effects, irritation at injection site

    ,photosensitivity • INTERACTIONS: decreased elimination of warfarin • CONTRAINDICATIONS: not safe in pregnant lactating and children

    below 8 yrs

  • KETOLIDE(TELITHROMYCIN)

    • Telithromycin has broad spectrum of activity against gram +ve bacteria ,active against most macrolide resistant pneumococci, but like erythromycin not active against staph aureus

    • INDICATION: for sinusitis, bronchitis , pneumonia • DOSAGE:800mg od daily dosage • ADVERSE EFFECTS: git side effects , vision problems ,

    hepatotoxicity, pseudomembrane colitis • INTERACTIONS: inhibitor of cyp3a4 • CONTRAINDICATIONS: decreased dosage in hepatic failure, no data

    for pregnant, lactating, children

  • OXAZOLIDINONES(LINEZOLID)

    • Outstanding activity against variety of gram positive organisms • Linezolid prevents formation of the 70S ribosome complex • No cross resistance • INDICAT/DOSAGE: at 10mg/kg iv/po for 10-14days is used as

    an alternative to vancomycin for MRSA pneumonia/enterococcal meningitis

    • Adverse effects: git side effects /oral moniliasis/ taste perverstion thrombocytopenia / myelosupression

    • Contraindications: pregnancy/lactation-caution .FDA has approved for treating infections in infants .NO contraindication in renal, hepatic failure

    • Interactions: MAO inhibitor

  • STREPTOGRAMINS (DALFOPRISTIN-QUINPRISTIN)

    • Good activity against MDR gram +ve organisms except enterococcal feacalis active against gram –ve URT pathogens

    • Inhibits protein synthesis by binding to 50s ribosome • Both are static drugs individually but cidal when used in combination, • StreA:streB—30%:70% • INDICATION: VRSA ORSA VR enterococcal feacium infections • DOSAGE: 7.5mg/kg IV ever 8-12hly for 7das • ADVERSE EFECTS: thrombophlebitis, arthralgias ,myalgias • INTERACTIONS: inhibits cyt p3a4 • CONTRAINDICATIONS: hepatic failure , not safe in children

    pregnant ,lactating women

  • GLYCO/LIPOPEPTIDE (DAPTOMCIN)

    • Bactericidal activity against wide variety of gran +ve bacteria including enterococi,staphylococci,streptococci that are even resistent to methicillin& vancomycin

    • Daptomycin bind to bacterial mambrane causes rapid depolarisation of membrane potential resulting in inhibition of dna rna protein synthesis

    • INDICATION: at dose of 4mg/kg iv od is approved for treatment of complicated skin infections

    • ADVERSE EFFECTS: git side effects , increased LFTS ,increased CPK with or with out myopathy

    • CONTRAINDICATIONS: renal failure ,inpregnant and lactitating no data

  • CARBAPENEMS(ERTAPENEM)

    • Effective against gram –ve bacteria and anaerobic bacteria • It inhibits cell wall synthesis • INDICATION: indicated only for community acquired

    infections because of its lack activity against pseudomonas • DOSAGE:1gm iv once aday • ADVERS EFFECTS: diarrhoea • seizeures(older,renal failure,cns

    pathology) • pseudomembrane colitis • CONTRAINDICATIONS: renal failure, no data in

    pregnant lactating and children

  • Why?

    •Increasing resistance patterns among both community and hospital acquire infections •Judicious use will prevent resistance strains to emerge

  • INDICATIONS

    1.Clinical scenario

    2.Organisms common in that scenario

    3.Antibiotic resistance patterns

    4.Pharmacokinetics of the drug

    5.Clinical trials

  • Community infections

    •Pneumonia

    •Meningitis

    •Osteomyelitis

  • COMMUNITY ACQUIRED PNEUMONIA

    Core pathogens

    •Streptococcus pneumonia •Mycoplasma pneumoniae (during epidemics) •Haemophilus influenzae •Staphylococcus aureus •Chlamydia pneumonia •Legionella pneumophila

    Pencillin resistance is a major problem in these cases So the drug used should take into account of the organism, risk factors for atypical organisms,anti biotic resistance

  • With no risk factors

    • Patient can be treated with

    • Ketolides(telithromycin)

    • New extended spectrum fluroquinolones

    • Ertapenem if there is e/o of vancomycin resistance

    Fluoro quinolene should not be used in patients with Rhinitis,sinusitis,Pahryngitis unless there is evidence of pneumonia……………ACP recommendation.

  • Meningitis

    Mc organisms

    • Strep.pneumoniae • H.influenza • Neisseria meningitidis • Streptococcus agalactiae • Listeria monocytogenes

    Pencillin resistance is also major problem

    So empirical therapy is started with 3rd generation cephalosporins But if risk factors are present for listeria ampicillin with gantamycin should be used as empirical therapy

    Cephalosporins are ineffective

  • AFTER GRAM STAIN AND CULTURE

    EMPIRICAL THERAPY CAN BE CHANGED TO

    MORE SPECIFIC THERAPY

  • In adults penetration of vancomycin is not good especially if dexamethasone is being used So in such cases ceftriaxone plus rifampcin is used

    Newer antibiotic LINEZOLIDE irrespective of dexamethasone therapy reaches high concenteration in CSF fluid so can be used in stead of ceftriaxone +rifampcin

  • Osteomyleitis

    Acute haematogenous infection : Staph.aureus

    Secondary to contagious focus of infection Polymicrobial: staphylococci, streptococci, enteric organisms, and anaerobic bacteria.

    P. aeruginosa is frequently associated with puncture wounds of the foot (especially by a nail through a sneaker)

    Penicillin-resistant, methicillin-sensitive (MSSA ) --- ceftriaxone, 1 g IV q24h

    Methicillin-resistant (MRSA ) --- Vancomycin

    Vancomycin alone always not effective in such cases. Rifampcin can be added New antibiotics like daptomycin is effective

    osteomyelitis due to Enterobacteriaceae ---- Extended spectrum β-lactam antibiotics fluoroquinolone

  • Hospital acquired infections

    Most common are

    •UTI

    •Pneumonia

    •Surgical site infections

  • UTI

    Mc organisms are E.coli, enterobacteracea enterococci pseudomonas

    Risk factors for uti include catheterization,instrumentation,diabetes Most are resistant to tmp-smx,amoxiciliin In such cases

    Fluroquinolones, extende spectrum b-lactams likeTicarcillin Carbapenem