Final exam: Antibiotics Flashcards
_______ Substance produced naturally in minute quantity by some microbes that has the potency to inhibit growth or kill other microorganisms.
Antibiotics
______ : an agent that affects physiology
drug
________ antimicrobial agent part synthesized in lab and part synthesized in microbe.
Ex: doxycycline, methcillin, ampicillin, amoxycillin
Semisynthetic antibiotic
the Advantages of ___1____
- is more affective against Gram negative bacteria cell,(Compared to gram postive)
- longer lasting with extended half life,
- easier to adminstor (compared to the natural ____1___)
1.antibiotics
______ antimicrobial agent synthesized in laboratory.
Ex: Isoniazid, sulfa drugs
Synthetic drug:
_______ is the trademark for isonictinic acid which is effective against M. tuberculosis
isoniazid
______ mode of actions, Plasma membrane injury: disruption of it’s function / integrity
Antibiotics mode of actions
______ mode of actions, Inhibition of cell wall synthesis : targets peptidoglycan
Antibiotics mode of actions
______ mode of actions, Blocking protein synthesis: due to structural differences of ribosomes (70S vs 80S)
Antibiotics mode of actions
______ mode of actions, Nucleic acid synthesis inhibition: targets enzymes
Antibiotics mode of actions
Ideal Properties of Antibiotics/ Antimicrobial Agents is ______, harm the microbe without significant damage to the host, shouldn’t be influenced by food or disease status
Selective toxicity
Ideal Properties of Antibiotics/ Antimicrobial Agents has ________, which means lowest dose toxic to the patient divided by High Tl and Low Tl.
Therapeutic index
Therapeutic index of _______ is less toxic to patients because they target unque structure point of bacteria cell.
High Tl
Therapeutic index of _______, need to be monitored carefully so does not to react toxic level
Low Tl
Ideal Properties of Antibiotics/ Antimicrobial Agents should be _______, be able to penetrate host tissue and reach microbial colony and must be effective at low, non toxic concentration to host
bio-available
Ideal Properties of Antibiotics/ Antimicrobial Agents should be ether ___1___, which stop bacteria growth then they are eliminated and ___2___ refer to bacteriolytic which also kills bacteria cell
- bacteriostatic
- Cidal
Ideal Properties of Antibiotics/ Antimicrobial Agents should be ______, should be stable in body fluids and exhibit therapeutic effect,
- not degraded by stomach acids
- antibiotics prone to inactivation in gastric environment should be given via i v / i m route
Stability
Ideal Properties of Antibiotics/ Antimicrobial Agents should be ______, drug action on various pathogens that varies, either broad or narrow spectrum
Spectrum of activity
Spectrum of activity of ______, agent targets microbes(Gram negative) from both taxonomic groups of bacteria which is critical in many life threatening situations
board spectrum
Spectrum of activity of ______, Disadvantages which they disturb normal microflora which normal flora prevents pathogen colonization, competiting for space attachment site nutrients O2 available. which causes super infection ; opens doors to transient pathogens
board spectrum
Spectrum of activity of ______, when antimicrobial action is limited to few microbe sps
Ex: Isoniazid affects only Mycobacterium sps and vancomycin
Narrow spectrum
Tissue distribution, metabolism and excretion of the drug: agents differ with regards to these properties, if you have bacteria infection of the brain or eyes, its a challege to treat because of the __________.
blood brain barrier (BBB)
Tissue distribution, metabolism and excretion of the drug: agents differ with regards to these properties. Antibiotics that are quickly remove by the _____ are good choice for treatment bacterial infection of bladder or urinary/urogen system
kidney
______ time it takes to eliminate one half of the original antibiotic dose in serum
- some antibiotics ( like Penicillin is 6 hours) have short half life
- additionally liver dysfunction / kidney disease, dose needs to be adjusted accordingly becos associated with slow metabolism and excretion of the drug
Half life
Combination of antimicrobials must exhibit some effect such as ______ is a two drugs given simultaneously, antimicrobial effect is greater than either given alone
- Ex:
- Streptomycin(enter easily composition of urine)
- penicillin(weaken the cell wall)
synergism
Combination of antimicrobials must exhibit some effect such as ______ contains sulfomethoxazole and trimethoprim which is given for UTI and AIDS patents
Septra/bactrim
Combination of antimicrobials must exhibit some effect such as ______, is a two drugs when given simultaneously, their action interfere with each other
- Ex:
- Tetracycline ( bacteriostatic)
- penicillin ( bacteriocidal, acts on growing cells, disrupting peptidoglycan) which means pushing and pulling
Antagonism
_______ drug combination that are neither antagonistic nor synergistic in action
additive
Side effects: undesirable effects on the host can manifest as _______, e.g. penicillin allergy 300 deaths / year; with fever, rash and / or anaphylactic shock
trigger of allergic reactions:
Side effects: undesirable effects on the host can manifest as ______, though selective toxicity such as ciprofloxacilin which is limited use in pregnant women and children. it affects cartilage development
exhibit toxic effects
______(Last Choice) causes aplastic anemia
chloramphenicol
______ (First Aid ointment) toxic to kidneys; so not useful for systemic use
polymyxin B :
______ forms Calcium complex, limits availability
tetracycline
_______ impairs balancing sense ; may cause irreversible deafness
streptomycin
disruption of the normal flora as in antibiotic associated pseudomembranous colitis, vaginitis and thrush is due to colonization by _______.
clostridum difficle
_______secretes toxins target intestinal epithial cells which becomes pseudomembrane patches that is made of dead cells, pus inflammation and clotted blood
clostridum difficle
_______ colonizes intestines of individual whose normal microflora being eliminated or distruped by antimicrobial chemotherapy (cramps, blood diarria)
clostridum difficle
yellow or green color ish on the teeth is cause by ______
tetracycline
_______ is due to hemoglobin breakdown product deposited on tongue papillal which is due to metronidazole intakes
black hairy tongue
Route of administration:can be via external or internal route such as ___1___: applied on skin directly and __2_____ administered via orally or intramuscularly
- Topical / local application
- Internal
Route of administration:can be internal route such as _______ simple, no needle or provider’s help
- Disadvantage: don’t follow time table
Orally
Route of administration:can be internal route such as _______ slow diffusion via blood vessels
- Disadvantage: high concentration can’t be achieved
Intramuscularly:
Route of administration:can be internal route such as _______ via needle or catheter can attain high concentration for limited time, directly to blood stream into liver
Intravascular
Antibiotic safety:prescribing antibiotic often involves assessing risk and benefits in the term of _______
therapeutic index
Often, another drug use may have a toxic effect that is not there when the _____ is taken alone Also, one drug may neutralize the intended effect of the other
1st drug (meaning 1 drug at a time)
few antibiotics dampens effectiveness of contraceptive pills hypersensitivity towards ______
penicillin antibiotic
______ should be given antibiotics that are considered safe as recommended by FDA. there should be no / minimal risk to the developing fetus
Pregnant women
Plasma Membrane Injury mediated mainly by the ________ antibiotics
polypeptide
_____ binds to the cell phospholipids; disrupts membrane structure alters membrane permeability cellulor content leak out and die
- limited to topical applications
Polymixin B
____: inserted into bacterial cytoplasmic membrane, which is useful in treatment of some Gr (+) ve bacteria resistant to other drugs ; not so effective against Gr (-)ve bacteria( because of the outermembrane)
Daptomycin
Cell wall acting antibiotics to ______ and ____
B-lactam and Non-Blactam
Cell wall acting antibiotics of B-lactam, ______ to penicillin group
lactamase sensitive
Cell wall acting antibiotics of B-lactam, ______, to semisynthetic penicillins, cephaloporins, monobactams and carbepenemes
lactamse resistant
Cell wall acting antibiotics of ________ are vancomycin, cycloserine and bacitracin
Non B-lactam
______: have narrow spectrum of activity, unstable in stomach acid environment; in contrast Pen V is stable and better absorbed
Natural penicillins
________ have broader specificity, have improved coverage and effectiveness against a wide range of organisms, including most streptococcal and staphylococcal species, aerobic gram-negative organisms, and many anaerobic organisms
Semisynthetic penicillins
______s are susceptible to penicillinase (β lactamase) which cleaves the β lactam ring ; antibiotic is inactivated and bacteria grows in the presence of antibiotic
Natural penicillin
______ interferes with the lnking enzymes and NAM subunits remain unttached to their neighbors, then the cell burst from osmotic pressure because the integrity of peptidoglycan is not maintained.
pencillin
Non β lactams of ______ binds to terminal amino acid of the tetrapeptide chain
- prevents cross linking ; weakens cell wall
- not effective against Gram (-)ve bacterial cells
- poorly absorbed
Vancomycin
Non β lactams of ______ inhibits peptidoglycan precursors (NAG and NAM)
- transport across membrane
- toxic, restricted for topical applications (first aid ointment)
Bacitracin
Non β lactams of ______ interfere with ala- ala bridge in Gr (+)ve bacteria cells if it lacks alanine amino acids
Cycloserine
_______ inhibits RNA synthesis binds and blocks prokaryotic RNA polymerase activity, Effective against Mycobacterium
Rifamycins :
___1____ and ____2___ :Inhibits DNA gyrase ( relieves strain caused by local uncoiling ) Effective against UTI pathogens and anthrax
- limited use in children and pregnant women’s
Ex: Ciprofloxacin, norfloxacillin and moxifloxacilin
- Quinolones
- fluoroquinolones
_______ ( Flagyl TM ) interferes with DNA synthesis and function selective toxicity only in anaerobic microorganisms becos active form binds to DNA used to treat bacterial vaginosis and C. difficle associated diseases
Metronidazole
______: a substance that prevents a cell from carrying it’s normal metabolic reaction, are structurally similar to normal used molecules
Antimetabolite
______ Functions in 2 ways:
- competitive inhibition of enzymes
- Ex: sulfanilamide and other sulfa drugs
- –by being erroneously incorporated into molecules like nucleic acids
- Ex: azidothymidine ( we’ll discuss later in HIV drugs )
Antimetabolite
antibiotics _____1__ Acquired ability to resist or block antibiotic action to which it is normally susceptible less drug used, controls evolution of ___1____ development
- resistance
How resistance is acquired and types ? _____
- mutation in chromosomal genes
- modification of the target site of antibiotic action
chromosomal resistance
How resistance is acquired and types ? _____ mainly due to R plasmids
extrachromosomal resistance :
________ code for enzymes that chemically modify the antibiotics
R Plasmid
________ carry 6-7 genes ; each confers resistance to different antibiotics, they can be transferred / acquired by one of the many genetic exchange processes (transduction or conjugation)
R Plasmid
How resistance is acquired and types ?_______ microorganism gets sequestered from antibiotics often temporary change ( loss of cell wall ) renders them non susceptible to antibiotic action
non-genetic resistance
_______ consequences, prolongs infection
Antibiotic Resistance
_______ consequences, delays recovery time, increases hospital and health care costs
antibiotic resistance
_______ consequences, needs more expensive and less effective toxic medications to cure infection
Antibiotic Resistance
_______ consequences,
causes higher mortality rates
Antibiotic Resistance
________ is longitudinal evolution, due to mutation in chromosomal DNA and advantageous to bacteria for survival
vertical evolution
________ is lateral evolution, due to R plasmid
horizontal evolution
The enzyme for penicilin to penicillionic is _____
B lactamase/penicillinase
Mechanism of Antibiotic Resistance that inactivation or destruction of the drug is ______
β lactamase
Mechanism of Antibiotic Resistance that Prevent antibiotic from reaching it’s target site / decreased uptake is Alteration of the membrane transport ________.
proteins/porins
Mechanism of Antibiotic Resistance that Alteration of drug target site / enzyme is ____1____.and ___2___ Ex. DNA gyrase, RNA polymerase
- Ribosomes
- Enzymes, Ex.DNA gyrase, RNA polymerase
Mechanism of Antibiotic Resistance that Rapid efflux of the drug, which Pumps the drug out of the cell before it can become _______
effective
Mechanism of Antibiotic Resistance that Development of alternate biochemical pathways common amongst the _______resistant strains which abandon sensitive steps
sulfonamide
Mechanism of Antibiotic Resistance are Survival and multiplication of a _____ variety
mutant
Alternate Practices to Reduce Antibiotic Resistanc is the Use of antibiotic should be _______
restricted
Alternate Practices to Reduce Antibiotic Resistance is the _______ should be performed prior to initiation of antibiotic treatment
Sensitivity tests
Alternate Practices to Reduce Antibiotic Resistance that the Full course of antibiotic treatment should be ________
followed
Alternate Practices to Reduce Antibiotic Resistance that the Use of left over or someone’s else antibiotics should be strongly _______
discouraged
Alternate Practices to Reduce Antibiotic Resistance that Educating general public about antibiotics use and their _______
advantages
Alternate Practices to Reduce Antibiotic Resistance which is Indiscriminate use should be ______ ( combination with alcoholic drinks, coffee and narcotics )
curtailed
PABA that goes through _____ into two pathway
E1, E2, E3 to folic acid
e1, e2, e3 to folic acid (this one is not susceptible)
sulfadrug
This is penicillin allergy, Pencillin is degraded into other breakdown product to ______ product
minor
This is penicillin allergy, Pencillin is degraded into penicilloyl to major, ______ product
abundant
This is penicillin allergy, Pencillin is degraded into penicilloyl to major, abundant product into a covalently binds with serum proteins that act as _______
haptens
This is penicillin allergy, Pencillin is degraded into penicilloyl to major, abundant product into a covalently binds with serum proteins that act as haptens will trigger ______ reactions
IgE mediated
Penicillin Allergy, 75% of allergic reactions is due to _______
penicilloyl haptens
Penicillin Allergy, 25% of reactions is due to other _______
breakdown products
Penicillin allergy, __1__ and ___2__ determinant refers to the frequency with which antibodies to these haptens appears / forms rather than the severity of the reactions.
- Major
- minor
Penicillin allergy, _______ reaction to penicillins is the most important and immediate danger connected with use of this antibiotic in some individuals
Acute anaphylactic