PID add to quiz 6 once cover this info

what is drug therapy?

Any medical treatment that utilizes one or more drugs to provide symptomatic relief, treat the underlying condition (metabolic, infectious) or act as a prevention for (other) diseases

what are 3 key properties of a drug?

• Selectivity (target vs non-desired targets)

• Concentrations (sufficient at the site of action vs toxicity)

• Time (maintenance vs depletion)

what is antimicrobial agent?

Any substance of natural, semisynthetic or synthetic origin that either kills microbes (bacteria,fungi, virus) or prevents their multiplication, reducing their pathogenic effect

whata re 4 different categories of antimicrobials?

antibiotics

antivirals

antiparasitic agents

antifungals

to interfere with bacterial cell life or growth what must abtibacterials do?

must interact with a vital structure or block a metabolic pathway (i.e., without causing direct toxicity for hosts receiving treatment)

what are 6 things antibiotics can target for bacteria?

cell wall

plasma membrane

ribosomes

metabolic pathways

DNA synthesis

RNA synthesis

what are 8 antibiotics that target bacteria cell wall?

B lactams

penicillins

cephalosporins

monobactams

carbapenems

Glycopeptides

vancomycin

bacitracin

what are 4 antibiotics that target bacteria DNA synthesis?

Fluoroquinolones

ciprofloxacin

levofloxacin

moxfloxacin

what are 2 antibiotics that target bacteria RNA synthesis?

Rifamycins

rifampin

what are 5 antibiotics that target bacteria plasma membrane?

polymyxins

polymyxin B

colistin

Lipopeptide

daptomycin

what are 3 antibiotics that target bacterias folic acid synthesis?

sulfonamides

sulfones

trimethoprim

what is 1 antibiotic that targets bacterias mycolic synthesis?

izoniazid

what are 6 antibiotics that target bacteria ribosome? which part of ribosome do they tag?

aminoglycosides (30S)

tetracyclines (30S)

macrolides (50S)

lincosamides (50S)

chloramphenicol (50S)

oxazolidinones (50S)

what are the 2 drug administration routes?

systemic

local

what are the 2 local ways to administer drugs?

topical

intramammary

what are the 2 systemic drug administration route categories?

enteral

parenteral

what are the 3 ways to administer drugs enterally?

oral

sublingual

rectal

what are 3 ways to deliver drugs parenterally?

inhalation

injection

transdermal

what is the main drug therapy priciple?

ADME principle

what is ADME principle?

1. Absorption (concentration in the blood)

2. Distribution (concentration in the tissues)

3. Metabolism (determination of metabolites)

4. Excretion (concentration in the feces/urine/others)

what is pharmacokinetics?

is the study of what the body does to the drug (absorption, distribution, metabolism, and excretion)

what is pharmacodynamics?

is the study of what the drug does to the body and the target (intensity of therapeutic -microbial death, and adverse effects)

what can pharmacokinetics and pharmacodynamics be thought as together?

s an exposure/response relationship

what is drug effect a function of?

dose and time

is response to drug often linear or nonlinear?

nonlinear

what is drug potency?

the concentration of drug at which 50% of the maximum effect is achieved

what are bactericidal agents?

kill bacteria and reduce the total number of viable organisms. Usually requires active growth.

what are bacteriostatic agents?

inhibit growth and replication of bacteria, thus allowing the host immune system to complete pathogen elimination

what are narrow spectrum i?

act against a limited group of bacteria

what are broad spectrum antimicrobials?

act against several groups of bacteria

(e.g. G+ & G- groups)

what is a drugs spectrum of activity based on?

the spectrum is based on the susceptibility of the wild-type population of bacterial species

how many widely accepted methods of antimicrobial susceptibility testing are there?

3

what decides which methods of antimicrobial susceptibility testing are standardized?

international committees

what are the 3 possible outcomes of antimicrobial susceptibility testing?

susceptible

intermediate

resistant

what are the 3 widely accepted antimicrobial susceptibility tests?

Kirby Bauer disc diffusion method

broth dilution method

gradient concentration diffusion strips

what is minimum inhibitory concentration of a drug (MIC)?

The MIC is defined as the lowest concentration of antibiotic that completely inhibits growth of the specific organism being tested.

what is minimum bactericidal concentration of a drug (MBC)?

The MBC is defined as the lowest concentration tested of an

antibiotic at which bacteria are killed

What are diameters of inhibition zones?

Reference susceptibility test that provides for the evaluation of the diameters of the inhibition zones around the disks containing the antibiotic tested

what are the 3 things are needed for the killing of a pathogen within a host by an antibiotic?

1. Binding to the target site in the bacterium

2. Sufficient concentration within the bacterium to adhere to enough targets

3. Sufficient time to cause effect

what are the 3 patterns antimicrobials can be classified by according to their activity pattern? what is each?

Concentration-dependent killing pattern: as more drug :: more effect.

Time-dependent killing pattern: the duration of exposure is what matters.

Hybrid pattern: both concentration and time matters.

what 3 parameters are breakpoints set according to?

• Microbiological (in vitro testing)

• Pharmacological (PK/PD indexes and response to treatment)

• Clinical (best evidence from literature)

what is acceptable daily intake (ADI)?

Defined as the daily intake of a substance which, over the entire lifetime of a human, appears to be without adverse effects or harm to the health of that human

what is maximum residue limits (MRLs)?

Defined as the maximum concentration of a drug residue in the animal consumable product that is legally tolerated

what is withdrawal period?

The time that must elapse between the last administration of a veterinary medicine and the slaughter or production of food from that animal, to ensure that the food does not contain levels of the medicine that exceed the maximum residue limit.

what are 8 categories of factors affecting drug choice?

infection

antimicrobial action and effect

host

toxicity

pharmokinetic drug properties

experience of veterinarian

cost

compliance

what are the 2 antibiotic resistance methods?

innate (natural) resistance

acquired resistance

what is innate resistance?

resistance through preexisting genomic property (mutation or gene)

what is acquired resistance?

resistance acquired by mutation or horizontal gene transfer (conjugation, transduction and transformation)

what is allowing antimicrobial resistance generation and dissemination to flourish?

Bacteria that have acquired resistance keep passing it to other bacteria. At the same time, antimicrobials keep killing bacteria that have no resistance, increasing the share of resistant bacteria

what are 7 things should do/consider when prescribing antibiotics?

• Rational antimicrobial use: actions that

prevent or minimize development of AMR

• Antimicrobial Stewardship: coordinated

programs design to implement appropriate

use of antimicrobials

• Use narrow-spectrum drugs when possible

• Culture and AST

• De-escalate antimicrobials when possible

• Follow treatment regimes and guidelines

• Search for alternatives!