Lec. 6: Antimicrobial Therapy Flashcards
Name the three major spectrums of antibiotics.
- Narrow
- Extended
- Broad
Name four extended spectrum antibiotics.
- Aminoglycosides
- Cephalosporins
- Imipenem
- Extended-spectrum penicillin
Name six broad spectrum antibiotics.
- Chloramphenicol
- Sulfonamides
- Tetracycline
- Trimethoprim
- Metronidazole
- Fluoroquinolones
Name seven narrow spectrum antibiotics.
- Penicillin G, V
- Erythromycin
- Clindamycin
- Vancomycin
- Polymixins
- Bacitracin
- Linezolid
What are the four main factors that affect antimicrobial therapy?
- Diagnosis of infecting organism
- Choice of antibiotic
- Local Factors
- Host Factors
What are the three categories associated with the choice of the antibiotic?
- Specificity and Spectrum
- Bacteriostatic vs. Bacteriocidal
- Concentration of antibiotic at the site of infection
Give five examples of local factors that affect antimicrobial therapy.
- Presence of pus
- Presence of Hb
- pH
- Anaerobic conditions
- Presence of foreign objects
Give seven examples of host factors that affect antimicrobial therapy.
- Integrity of host defense mechanism
- Age
- Renal and liver function
- Genetic factors
- Pregnancy, nursing
- Drug allergy
- Genetic factors
Both bactericidal and bacteriostatic agents rely upon ? to aid in eliminating the pathogen.
Host defenses
A good rule of thumb to go by when classifying antibiotics as bactericidal or bacteriostatic is that most ? drugs are bacteriostatic and must ? and ? drugs are bactericidal. Name the one exception.
- Broad Spectrum
- Narrow Spectrum
- Extended Spectrum
- Metronidazole is the exception. It is a broad spectrum drug, but is classified as a bactericidal antibiotic.
What are bactericidal antibiotic preferred (4 reasons)?
- Reduces the # of microorganism
- More rapid acting
- Produces irreversible damage
- Complete organism killing is required in some cases
Bactericidal antibiotics make it easier for the host defense to kill all bacteria by ?.
By reducing the # of microorganisms
Why do we want the bactericidal antibiotic to produce irreversible damage?
So you do not have to maintain MIC (minimum inhibitory concentration) for killing effect
Name three examples where bactericidal antibiotics complete organism killing is required.
- Bacterial endocarditis
- Meningitis
- Deficient or suppressed immune defenses (AIDS, chemo/transplant patients)
What are the four factors associated with the concentration of antibiotic at site of infection?
- Dosage and duration of therapy
- Route of administration
- Distribution, metabolism, excretion
- Patient compliance
Who is considered the father of chemotherapy, proposed the idea of drugs as “magic bullets,” and developed arsenic compounds for the treatment of spyhilis?
Paul Ehrlich
T or F. (1) Drugs can be found/developed that will specifically target the site of action on parasite. (2) These sites of action should be present in the organs and tissues of the host.
- True
2. False. These sites of action should NOT be present in the organs and tissues of the host.
Name eight sites of action for antibiotics.
- Cell wall synthesis
- Folic acid metabolism
- Cell membrane
- Protein synthesis (tRNA)
- DNA gyrase
- DNA-directed RNA polymerase
- Protein synthesis (50s inhibitors)
- Protein synthesis (30s inhibitors)