Chemoprophylaxis

1. CHEMOPROPHYLAXIS Dr Sangeetha P

2. CHEMOPROPHYLAXIS Definition The Practice of administering an antimicrobial agent for preventing an infection or for suppressing contacted infection before the clinical manifestations .

3. Influencing factors

4. . Single pathogen Acute exposure Short duration prophylaxis Suitable drug Lethal disease Prophylaxis effective when

5. Ineffective prophylaxis leads to Overuse of antibiotics Resistant organisms Economic waste Risk of side effects

6. The ideal antibiotic Narrow spectrum Cheap Minimum toxicity Single dose..

7. Types of prophylaxis

8. Classification

9. Disease targeted prophylaxis Rheumatic fever Endocarditis Malaria Cholera Plague Influenza

10. Host targeted HIV Neutropenia Asplenia Haemoglobinopathy

11. Post exposure Tuberculosis Pertussis HIV Meningococcal meningitis

12. Surgical prophylaxis To prevent Surgical Site Infection (SSI); not all infections occuring in the post-op period.. Staphylococcus - Cefazolin

13. Rheumatic fever Primary Treating streptococcal pharyngitis Secondary Preventing a second episode of pharyngitis

14. Streptococcal pharyngitis Oral Penicillin V for 10 days Oral Erythromycin for 10 days Inj Benzathine Penicillin 6L IM single dose

15. Secondary Oral Penicillin V 250mg BD daily Sulfadiazine 500mg OD Erythromycin 250mg BD Inj.Benzathine Penicillin 1.2L IM 4 weekly

16. Endocarditis High morbidity Dental /Surgical procedures with bleeding from mucosa.. 2007 AHA guidelines Choice of drug depend on the flora..

17. Endocarditis . Upper GIT Alpha hemolytic streptococci Ampicillin / Amox / clindamycin

18. Endocarditis . Lower GIT ENTEROCOCCI Ampi+Genta Vanco+Genta Ampi / Amox

19. Antibiotic Regimens for Prophylaxis of Endocarditis in Adults with High-Risk Cardiac Lesions A . Standard oral regimen   1. Amoxicillin 2.0 g PO 1 h before procedure B . Inability to take oral medication   1. Ampicillin 2.0 g IV or IM within 1 h before procedure C. Penicillin allergy   1. Clarithromycin or azithromycin 500 mg PO 1 h before procedure   2. Cephalexin 2.0 g PO 1 h before procedure   3. Clindamycin 600 mg PO 1 h before procedure D. Penicillin allergy, inability to take oral medication   1. Cefazolin or ceftriaxone 1.0 g IV or IM 30 min before procedure   2. Clindamycin 600 mg IV or IM 1 h before procedure

20. Malaria Tab.Chloroquine 500mg base once weekly. Start 2 weeks prior & continue for 4weeks after travel.. Chloroquine sensitive

21. Malaria Atovaquone+Proguanil ( Malarone ) daily Mefloquine 250mg weekly Doxycycline 100mg daily Chloroquine resistant

22. Tuberculosis Treatment of latent infection..

23. Regimens INH 300mg daily for 9 months or INH + Rifampicin daily for 6months or Rifampicin for 4 months Rifampicin + Pyrazinamide for 2 months.

24. HIV-Post exposure prophylaxis Two drug regime for low risk Zidovudine + Lamivudine Zidovudine+Lamivudine+Indinav ir Three drug regime for high risk

25. HIV Prophylaxis against opportunistic infections: primary Disease Drug TB INH PCP COTRIMOXAZOLE TOXOPLASMA COTRIMOXAZOLE MAC AZITHRO/CLARITHRO VARICELLA ACYCLOVIR

26. Secondary or c/c suppressive Rx . Disease Drug PCP Co- trimoxazole Toxoplasma Co- trimoxazole MAC Azithromycin CMV Gancyclovir / foscarnet / cidofovir Cryptococcosis Fluconazole Salmonella bacteremia Ciprofloxacin

27. OTHERS Disease Drug Meningococcal meningitis Ceftriaxone / Rifampicin /C iprofloxacin Pertussis Erythromycin Cholera Tetracycline Plague Doxycycline Syphilis Ceftriaxone Recurrent UTI Cotrimoxazole Recurrent genital herpes Acyclovir

28. Surgical prophylaxis To prevent Surgical Site Infection (SSI) Maintain peak concentration of antibiotic at time of wound closure

29. Surgical prophylaxis Principles Give antibiotics 1 hour before surgery Continue for 24 hours only Most commonly cephalosporins

30. Types of surgical wounds .

31. Type Example Clean Elective, no viscera or tract entered. Neurosurgery Clean contaminated Opening of viscera with minimal spillage GI Surgery Contaminated Gross spillage.Non purulent inflammation Gut resection Dirty Purulent Opening of an abscess

32. Drugs used Surgery Organism Antibiotic Clean Staphylococcus Cefazolin Clean contaminated Head&neck Oral anaerobes Cefazolin+Clindamycin Clean contaminated colorectal Anaerobes Neomycin,Cefoxitin Dirty Anaerobes ,Gram negative aerobes Cefoxitin,Gentamycin

33. High risk when Surgery >2hours Prosthesis Immunosuppressed patient Extremes of age..