Antibacterial Overview Flashcards
Bacteriostatic
stops the growth of the organism and we hope that the immune system takes over
Bacterocidal
Kills the organism
Gram Positive Cocci (ex)
Strep pneumo
Strep pyogenes
Staph aureus (MSSA - MRSA)
Gram Negative Cocci (ex)
Neisseria meningitidis
Neisseria gonorrheae
Gram positive rods (ex)
listeria
gram negative rods (ex)
E. coli
H. influenzae
Pseudomonas aeruginosa
M. catarrhalis
Anaerobes (ex)
Clostridium difficile Clostridium tetani Clostridium botulinum Bacteroides fragilis H. Pylori
Atypical Organisms (ex)
Chlamydia
Mycoplasma
Bacterocidal drugs target:
the cell wall, the cell membrane or DNA/RNA synthesis/function
Bacterostatic drugs target:
protein synthesis (cant grow but doesnt die) Folic acid metabolism
“Natural resistance” means…
the microbe lacks the drug’s target in its natural state
“escape resistance” means…
microbes are sensitive and the drug reaches the target, but the organism has found a loophole
“Acquired resistance” means…
The microbe has produced generations of organisms with traits that minimize drug action. Proper dosing and duration of drug must be met
4 ways to be resistant to a drug
alteration of the target increasing the efflux learn how to bypass the pathway that is waiting for you enzymatic degradation (of drug
Bacterocidal agents are preferred in severe infection
:)
bacterocidal agents act more quickly and irreversibly
:)
Bacterocidal agents compensate for immunocompromised patientes
:)
Bacterocidal agents are required for treatment of infections in locations that are not accessible to immune system
endocarditic vegetations, cerebrospinal fluid
Readily enter CSF
sulfonamides-trimethoprim
3rd/4th generation cephalosporins
Rifampin-metronidazole
beneficial accumulation into bone
Clindamycin
beneficial accumulation into pulmonary cells
Macrolides
Beneficial accumulation into sebum (acne) and gingiva (peridontitis)
Tetracyclines
Beneficial accumulation into urine
Nitrofurantoin
Toxic accumulation in inner ear and renal brush border
Aminoglycosides
Toxic accumulation into the Ca++ of developing bone and teeth
Tetracyclines
Drugs that are renally eliminated need to be dosed differently in those with decreased kidney function
Monitor their serum creatinine and creatinine clearance
Hepatic metabolized drugs can’t be “hepatic dosed” in those patients that have liver dysfunction
Be cautious in these cases or use a different drug
Drugs you DONT want to use in the hepatic dysfunction patient: DQ-CRIMES
Doxycycline Quinolones Clindamycin Rifampin Isoniazid Metroniadazol Erythromycin Sulfonamides
Narrow Spectrum means…
effective against EITHER gram positive OR gram negative organisms
Extended spectrum means…
effective against gram positive AND gram negative
Broad Spectrum means…
effective against: gram positive, gram negative and atypical organisms
Acute severe infections should be treated with broad spectrum with targets towards likely pathogens
:)
Adverse reaction: direct toxicity means…
Drug effect on microbes effects host cellular process too. Related to MOA
Adverse reaction: Indirect toxicity
allergic reactions or hypersensitivity. NOT related to MOA
Adverse reaction: disturbance of host flora
more commonly associated with broad spectrum drugs
