Chapter 15: Antimicrobial Drugs Flashcards
Antimicrobial Drugs
therapeutic compounds that kill microbes or inhibit their growth; categorized based on the pathogen they target
Alexander Fleming
1928; studied staphylococcus aureus; notived a plate was contaminated with mold; also noted that S. aureus was unable to grow near the mold; fleming determined that the mold excerted a compound that could inhibit the bacteria
Broad Spectrum Drugs
effective against both gram negative and positive bacteria
Narrow Spectrum Drugs
target a limited range of bacteria; usually preferred because they present less disruption to the normal microbiota
Bacteriostatic
prevent bacteria from growing; tend to target bacterial protein synthesis and metabolic pathways
Bactericidal
kill bacteria; tend to target bacterial cell walls or cell membranes and nucleic acids
A drugs bactericidal or bacteriostatic properties can change based on…
pathogen type, dose, length of drug regimen, pathogen load, route of administration
Drawbacks to Bactericidal Drugs
kills normal microbiota; can lead to a spike in bacterial toxin release that can be deadly (LPS)
Antibiotics
naturally occuring antimicrobial compounds
Synthetic Antimicrobials
manufactured by chemical processes
Semisynthetic Antimicrobials
chemical modification of naturally occurring antibiotics
First Generation Drugs
drugs taht result from a first round of chemical modification
Second Generation Drugs
drugs resulting from a second round of chemical modification
Therapeutic Index
ratio of the macimum tolerated or safe dose to the minimum effective therapeutic dose; high therapeutic index is considered safer than a drug with a narrow therapeutic index; therapeutic index= max safe dose/min effective dose
Therapeutic Drug Monitorying
used to ensure patient well being and/or assess teh therapeutic benefit of a drug; may involve monitoring- measuring drug concentrations in the blood or monitoring patient parameters; used in late pahse clinical trails to ensure drug safety
Toxicity Considerations
kidneys and liver are key organs taht metabolize and eliminate drugs; susceptible to damage by certain drugs
Nephrotoxic
kidney-toxic; antimicrobials are a leading cause of drug associated nephropathy; aminoglycosides and extended use of nonsteroidal anti-inflammatory drugs (NAID)
Hepatotoxic
antimicrobial drugs can induce liver damage; drug-induced liver injury (DILI); liver is fairly resilient organ taht tends to recuperate after the drug regimen is stopped; DILI is most commonly cited reason for discontinuing drug development or removing a drug from the amrket
Oral Administration
preferred bc it is easiest; must be-stable in acidic environment of the stomach; sufficiently absorbed in the intestines
Parenteral Administration
injection or infusion; downsides-needles and/or intravenous lines must be used; requires basic medical training; needle phobia or injection discomfort
Half Life
time it takes for half of a dose to be eliminated or deactivated by the body; half life determines frequency of administration if it is short requires frequent administration and long not taken as frequently
Beta-lactam Antimicrobials
block cell wall construction; contain a four sided beta lactam ring; bind to transpepidase enzymes; prevent protein cross links that bind peptidoglycans carb chains together
Beta-Lactam Antimicrobial Examples
penicillins; cephalosporins; carbapenems; monobactams
Beta-Lactamases
enzymes created by some bacteria that inactivate beta-lactam
Beta-Lactamase Inhibitorys
combat beta-lacatmases; inhibitors contain a beta lactam ring structure that binds strongly to beta-lactamase; ex- clavulanate, sulbactam or tazobactam, augmentin (combo of amoxicillin and clavulanate)
