Antibacterial Agents Flashcards
1
Q
What are the B-lactams?
Are they -cidal or -static?
What is their mechanism?
A
Penecillins
Cephalosporins
Carbapenems
Aztreonam
-cidal
Bind to PBP and inhibit transpeptidation
So, inhibit an enzyme
2
Q
SE of penicillins
A
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
3
Q
Penicillin G
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Narrow spectrum: G+
Natural penicillin
Route: IV or IM–hydrolyzed w/ stomach acid
Given w/ procaine to slow release
Destroyed by B lactamase
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
4
Q
Penicillin V
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Narrow spectrum: G+
Route: Oral
Natural penicillin
Absorption unpredictable
Destroyed by B lactamase
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
5
Q
B lactamase resistant penicillins
Name and spectrum
A
Nafcillin
Oxacillin
Cloxacillin**
Dicloxacillin**
Methicillin
“Nafcillin and -oxacillin”s
NAFcillin=Not AFfected by penicillinase
- Oxacillin’s=Ox is resistant to penicillinase*
- Methicillin too but not in use anymore*
Narrow spectrum
6
Q
Nafcillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
B-lactamase resistant
Narrow spectrum: G+
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
NAFcillin=Not AFfected by penicillinase
7
Q
“-oxacillin”s
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
B-lactamase resistant
Narrow spectrum: G+
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
OXacillin=OX is strong animal, resistant to penicillinase
8
Q
Methicillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
B-lactamase resistant
Narrow spectrum: G+
Does not readily enter CNS
Do not use anymore-too toxic
9
Q
Broad or extended spectrum penicillins
A
Amoxicillin
Ampicillin
Ticarcillin
Piperacillin
Mezlocillin
Carbenicillin
TAMPAC
10
Q
Amoxicillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Route: Oral
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- B lactam ring may inh. GABAergic neurons
11
Q
Ampicillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Does not readily enter CNS
SE:
- Rash in pts who have mononucleosis +other viral inf.
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
12
Q
Ticarcillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
13
Q
Piperacillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
14
Q
Mezlocillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
15
Q
Carbenicillin
A
Tx: Antibacterial
Mech: Bind to PBP→inh. transpeptidation
inhibit an enzyme
Broad spectrum
Does not readily enter CNS
SE:
- Allergic rxns→anaphylactic shock
- High IV doses→seizures
- B lactam ring may inh. GABAergic neurons
16
Q
Sulbactam
A
Mech: Bind to and inh. B lactamase
Non antibiotic B-lactam ring compounds
17
Q
Clavulanic acid
A
Mech: Bind to and inh. B lactamase
Non antibiotic B-lactam ring compounds
18
Q
Augmentin
A
Amoxicillin+clavulanic acid
19
Q
Timentin
A
Ticarcillin and clavulanic acid
20
Q
Unasyn
A
Ampicillin and sulbactam
21
Q
What’s the difference b/w each generation of cephalosporins?
A
Succeeding generation has:
- more G- activity (broader spectrum)
- More res. to B lactamase
22
Q
Cephalosporins
A
cef or ceph
SE:
- Allergic cross activity w/ penicillin sensitive pts
- Possibility of superinfection
23
Q
Carbapenems
A
Tx: Antibacterial–mixed infections
Penicillin analog
Small penicillinase resistant B lactam
Spectrum: Very broad
Route: IV
SE:
- Can enter CNS→Seizures
24
Q
Imipenem
A
Tx: Antibacterial–mixed infections
Class: Carbapenem
Penicillin analog
Small penicillinase resistant B lactam
Spectrum: Very broad-Better against G+
Route: IV
SE:
- Can enter CNS→Seizures
- Metabolized in kidney to nephrotoxic product
- Given w/ cilastatin which inh. enzyme that produces toxic product
25
Meropenem
Tx: Antibacterial--mixed infections
Class: Carbapenem
Penicillin analog
Small penicillinase resistant B lactam
Spectrum: Very broad-**Better against G-**
Route: IV
SE:
* Can enter CNS→Seizures
26
Cilastatin
Given w/ **impenem**
Prevents nephrotoxic product by _inh. enzyme_
27
Aztreonam
Antibacterial
Class: Monobactam
Route: IV or IM
Not affected by lactamases
Spectrum: Aerobic G- organisms
_Not_ cross reactive w/ allergic pts
SE:
* Seizures
28
Vancomycin
Antibacterial
**Class**: Non B lactam CW inhibitors
**Mech**: Binds to _dialanine residue_ on CW and prevents cross linking
**Use**: Severe infection in which B lactams can't be used
Primary alt. to penicillins for staph infections.
**Spectrum**: G+
**Route**: IV--unless target in gut (pseudomembranous colitis)
SE:
* Nephrotoxicity
* Ototoxicity
* If given rapidly via IV→histamine release→Redman or red neck syndrome
* Flushing
* Rash
* Itching
Resistance:
* Target changed
* Dialanine changed to lactic acid
*Dr. Van Ron*
***D**ialanine **R**esidue. **Van**comycin. **R**edman. **O**totox. **N**ephrotox*
29
"-vancin"s
**Televancin**
**Dalbavancin**
Antibacterial
**Class**: Non B lactam CW inhibitors
Lipoglycopeptide
**Mech**: Binds to _dialanine residue_ on CW and prevents cross linking + disrupt bacterial CM
SE:
* Nephrotoxicity
* Fetal damage
* Metallic taste
30
Bacitracin
Antibacterial
**Class**: Non B lactam CW inhibitors
Polypeptide
**Mech**: Inh. recycling of bactoprenol carrier
**Spectrum**: G+
**Route**: Topically--very toxic
SE:
* Nephrotoxicity--if not given topically
31
Fosfomycin
Antibacterial
**Class**: Non B lactam CW inhibitors
**Mech**: Blocks synth of NAM
**Spectrum**: Aerobic G-
**Use**: Uncomplicated UTI
SE:
* Diarrhea--killing bacteria in gut
32
Cycloserine
Antibacterial
**Class**: Non B lactam CW inhibitors
**Mech**: Inh. incorporation of alanine into NAM
_Enzyme inhibitor_
Used against mycobacterium TB
SE:
* CNS
* Sedation
* Tremor
* Psychosis
* Cyclo- gives you psycho-*
* Go to war in **NAM**, when you come back you have **PTS**d*
* Psychosis*
* Tremors*
* Sedation*
33
Erythromycin
Antibacterial
**Class**: Macrolides-inhibit protein synth
-static
**Mech**: Reversibly binds to 50s subunit and inh. translocation of mRNA
Inh binding of tRNA to P site
**Spectrum**: G+
SE:
* GI upset, nausea, and heartburn
* Increase in GI activity b/c activates motilin
* Inh P450
* Liver damage
* Arrythmias
*macROlides like erythROmycin inh. transLOcation*
***M**otility*
***A**rrythmia*
***C**holestatic hepatitis (liver tox)*
***R**estricts P450*
***O**totoxicity*
34
Clarithromycin
Antibacterial
**Class**: Macrolides-inhibit protein synth** **
_Oral stability_
vs. Helicobacter Pylori
* macROlides like erythROmycin inh. transLOcation*
***M**otility*
***A**rrythmia*
***C**holestatic hepatitis (liver tox)*
***R**estricts P450*
***O**ral stability/**O**totoxicity*
35
Azithromycin
Antibacterial
**Class**: Macrolides-inhibit protein synth** **
_Longer T1/2_ (3 days)
*macROlides like erythROmycin inh. transLOcation*
***M**otility*
***A**rrythmia*
***C**holestatic hepatitis (liver tox)*
***R**estricts P450*
***O****totoxicity*
36
Telithromycin
Antibacterial
**Class**: Macrolides-inhibit protein synth** **
Same sites as erythromycin (50s) but _induces less resistance_ b/c not readily transported out of bacterial cell
SE:
* GI upset, nausea, and heartburn
* Increase in GI activity b/c activates motilin
* Inh P450
* Liver damage-_SEVERE liver toxicity_
* Arrythmias
* _Block cholinergic receptor_
* Worsen myasthenia gravis
* Inh long ciliary ganglion→Decrease visual accomodation
*macROlides like erythROmycin inh. transLOcation*
***M**otility/ **M**yasthenia gravis worsens*
***A**rrythmia*
***C**holestatic hepatitis (liver tox)*
***R**estricts P450*
***O**cular inh./**O**totoxicity*
37
Streptomycin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
**Spectrum**: Aerobic G-
Must be absorbed by active transport
**SE:**
* Ototoxicity
* Hearing and balance affected
* hearing loss may be permanent
* Nephrotoxic
* Most common cause of drug induced renal failure
* Used very widely
* High doses
* Neuromuscular blockade
* Decrease in ACh+ ACh receptors on mm
* Fetal damage
* _Preg cat. D_
__
* Strippers fornicate*
* Strep. FORNICAT*
***F**etal damage*
***O**totox.*
***R**enal tox*
***N**egative (G-)*
***I**rr. bind 30s*
***C**idal*
***A**Ch block *
***t**RNA can't bind to mRNA*
* *
38
Aminoglycoside antibacterial agents
*Names and mech*
**Streptomycin**
Gentamycin
Tobramycin
Neomycin
Amikacin
Kanamycin
Netilmicin
***_Kan_**ye's _Cobra_ **_A_**rose **_Gent_**ly as **_N_**aughty **_Nat_**alie _Stripped_*
***_Kan_**amycin **_Tobra_**mycin **_A_**mikacin **_Gent_**amycin **_N_**eomycin **_Netil_**mycin **_Strept_**omycin*
**Mech**: Irr bind to 30s subunit
Can inh. or alter tRNA binding along mRNA including initiation site
Irr. mRNA misreading=bacteri**_cidal_**
39
Gentamycin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
_**Use: **Ointment for eye_
40
Tobramycin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
41
Neomycin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
Route: Topical or oral
_**SE: **Very nephrotoxic_*--so only topically or orally*
42
Amikacin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
43
Kanamycin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
44
Netilmicin
Antibacterial
**Class**: Aminoglycosides-inhibit protein synth** **
**-cidal**
**Mech**: Irr. binds to 30s subunit
Inh. or alter tRNA binding along mRNA including initiation site
_DROPPED in the US_
45
Tetracycline
Tx:
* Rickettsia
* Spirochetes (lyme disease)
* Helicobacter
* Legionella
Mech: Reversibly bind to 30s.
Inhibits the binding of tRNA to the A site
-static
SE
* Deposited in Ca storage sites-bones/teeth-esp fetus or child
* Binds to cations, esp Ca, also Fe and Al.
* Preg risk D
* Renal and hepatic toxicity
* Degrades to toxins--don't use after expiration date
46
Other cyclines vs tetracycline
Less likely to bind Ca+
47
Chloramphenicol
Antibacterial agent
Mech: inh. peptidyl transferase
SE:
* Inh. P450
* Can cause aplastic anemia
* Hemolytic anemia too (said this in the review)
* Gray baby syndrome
* Metabolized by a phase II enzyme that is not active in newborns.
* Can't metabolize it→baby turns blue and circulatory system inhibited
48
Clindamycin
Antibacterial agent--lincosamide
Mech: like erythromycin-inh. translocation
SE: Severe superinf. w/ C. dificile
Targets:
* Severe anaerobic infections (penetrating gut wound)
* Dental prophylaxis in pts w/ heart valve problems
49
Lincomycin
Antibacterial agent--lincosamide
Mech: like erythromycin-inh. translocation
SE: Severe superinf. w/ C. dificile
Targets:
* Severe anaerobic infections (penetrating gut wound)
* Dental prophylaxis in pts w/ heart valve problems
50
-pristin
**Quinupristin** (A+P site)
**Dalfopristin** (P site)
Mech: Inh. A and P sites
Always used together--synergistic
SE: Muscle pain
Spectrum: G+
51
-zolid
Linezolid
Tedizolid
Mech: Inh. binding of fmet (start codon) tRNA to P site
Prevents initiation of protein synth.
SE
* Anemia
* Pseudomembranous colitis
* Will happen w/ any powerful AB b/c of C. dificile
52
Daptomycin
Antibacterial agent--lipopeptide
Mech: Forms pores in bacterial CM
Targets: Aerobic G+ (staph, strep)
Skin and soft tissue inf. or severe blood inf w/ S. aureus
SE:
* Muscle pain and weakness
* *careful w/ statins*
* Eosinophilic pneumonia
53
Fidaxomycin
Antibacterial agent
Mech: Inh. C. dificile RNA pol
Orally--Not systemically absorbed
Target: C. dificile
54
-floxacin
Antibacterial agent
Mech:
* Inh topoisomerase II (DNA gyrase)
* Inh topoisomerase IV
No effect on mammalian topoisomerase
SE:
* May damage developing cartilage
* Not for children or pregnant women
* Tendonitis--achilles tendon rupture
* Phototoxicity (drug in skin responds to sunlight)
* May worsen myasthenia gravis
* Peripheral neuropathy *(said it in review along w/ retinal detachment)*
Spectrum: Broad--G+,G-, Acid fast
55
Sulfisoxazole
PABA\*→folic acid→DHFA\*\*→THFA
\*→=Dihydropterate synthetase
\*\*→DHFR
Mech: Reversible inh. dihydropterate synthetase
For UTIs
SE:
* Allergic whole body rash (Stevens Johnson syndrome)
* Hemolytic anemia in G6PDH deficient pts
* Megaloblastic anemia
*Sulfa drugs have sulf or sul*
56
Trimethoprim
Antibacterial agent
Mech: Inh. DHFR (like methotrexate)
Specific for bact. enzyme
*Used in conj. w/ sulfamethoxazole *
SE:
* Megaloblastic anemia
* Can be avoided w/ leucovorin
Targets:
* G- bacteria
* UTIs
* Concentrates in acidic prostate and vaginal tissue
57
Metronidazole
Mech: Prodrug-converted to a free radical active molecule by obligate anaerobic bacteria
Route: IV for severe anaerobic bacterial inf.
Use: Protozoal inf:
* Trichoma (STD)
* Giardia (from water)
SE:
* Seizures
* Peripheral neuropathy
58
Nitrofurantoin
Mech: Reduced by bacteria to a highly reactive molecule
Concentrates in urine
Use: UTI
SE:
* Cough
* Chest pain
* Brown urine
59
Polymixin B
Antibacterial agent
Mech: Binds to negatively charged sites on LPS of G- bact
→to memb. permeability
Route: Topical
SE: (all reversible)
* Nephrotoxic
* Neurotoxic
* Neuromuscular blockade
* Ataxia
* Perioral paresthesia
* Poly mixes in her PANNNN*
* Polymixin B. **P**erioral paresthesia. **A**taxia. **N**eurotoxic. **N**ephrotoxic. **N**euromuscular blockade. binds to **N**egatively charged sites on LPS*
60
Gramicidin
Antibacterial agent
Mixture of 3 diff peptide AB
Mech: forms pores in bacterial CM
Route: topical
NEVER give IV--toxic
Spectrum: G+
61
Retapamulin
Antibacterial agent
Mech: inh. peptidyl transferase
Route: Topical
Use: skin staph or strep inf.
62
Mupirocin
Mech: Binds to bacterial isoleucyl tRNA synthetase
Route: Topical
Use: Staph inf.
63
Neosporin
Neomycin+ polymixin +gramcidin
64
Polysporin
polymixin+ bacitracin
65
Polytrim
Trimethoprim+ polymixin
66
Terak
oxytetracycline+ polymixin
67
Isoniazid
Antimycobacterial agent
Mech: Produces inh. of multiply mycobacterial enzymes
Inh CW synth
Prodrug
Cidal, but static for dormant cells
Used alone for prophylaxis--in combo for active tx
Metabolized by acetylation--slow acetylators affected
SE:
* Increase excretion of vit B6→pyroxidase deficiency→niacin deficiency
* Pellegra
* Peripheral neuropathy
* Optic neuritis
* Hepatotoxicity
*Isoniazid is IHOPPIN*
***I**nh. mycobacterial enz.*
* **H**epatotox.
* *O**ptic neuritis.*
***P**eripheral neuropathy + Pellegra. *
***P**rodrug + Prophylaxis*
***I**ncrease excretion of vit B6→→*
***N**iacin def.*
68
Rifampin
Antimycobacterial agent
Antibacterial agent
Mech: Inh DNA dep. RNA polymerase
-cidal
SE:
* Hepatic toxicity
* Red color in all body fluids
* Induces P450--very strong
* Can metabolize BC!
Rifampin=red
Will metabolize BC (induce P450) so the sperm will LIVEr
69
Pyrazinamide
Antimycobacterial agent
Mech: Inh FA synth
Prodrug converted in macrophase where TB lives
SE:
* Gout
* Hepatitis
70
Ethambutol
Antimycobacterial agent
Mech: Inh arabinosyl transferase
Necessary for CW synth
SE:
* Optic neuritis
* Impaired red/green discrimination
* Decreased vision
71
Bedaquiline
Antimycobacterial agent
Mech: inh. mycobacterial ATP synthetase
Always used w/ 3 other anti-TB drugs
SE:
* Arrythmias
* Increase incidence of death
*You're in your _bed_ **_MAST_**urbating your _erection (arrection)_ *
***_Bed_**aquiline. **M**ycobacterial **A**tp **S**ynthe**T**ase. _Arrythmia_.*
72
Dapsone
Antimycobacterial agent
Related to sulfonamides
Mech: Reversible inh. dihydropterate synthetase
Use: For mycobacterium leprae (leprosy
73
Antimycoplasma agents
NO CELL WALL!
So use non CW inhibitors:
Erythromycin
Tetracycline
74
