Drugs one last time Flashcards
The Ultimate List
B-lactam antibiotics function, categories, structure
- Disrupt cell wall to allow for water to flood in and cause the cell to burst
- PCNs, cephalosporins, carbapenums, and aztreonam
PCN mechanism of action
Bind to penicillin binding proteins and cause inhibition of transpeptidases and activation of autolysins
PCN is mostly affective against gram…
positive organisms
Most common ADR to PCN
Allergic rxn, approx 7%
How organisms have developed resistance to PCN
- B-lactamase production
- PCN can’t reach PBPs
- PBP’s with low affinity
PenG is active against…
- Gram + bacteria except for highly resistant ones
- Some gram neg including niesseria, also DOC for syphilis
PenG specrum
Narrow
PenG administration
4 diff salts, none activated PO
PenG elimination prolongation is caused by what?
Probencid
What 2 drug classes should never share IV?
PCN and aminoglycoside, inhibit each other when distributed together, synergistic when administered separately
PenV
-Identical version of PenG but has resistance to gastric acid so is the go to standard for oral therapy
Nafcillin, oxacillin, dicloxacillin spectrum
Very narrow, only penicillinase producing strains of S. aureus and S. epidermidis
Aminopenicillins include…
Ampicillin, amoxicillin
Ampicillin and amoxicillin antimicrobial spectrum
Most gram + organisms, some gram - including Haemophilus, Escherechia coli, Salmonella, Shigella, E. faecalis
Most commoon amoxicillin ADR
Amoxicillin rash, nonallrgic maculopapular rash not serious
Piperacillin spectrum
Pseudomonas aeruginosa, enterobacter, bacteroides fragilis, klebsiella, as well as most gram + and some other gram -
3 common B-lactamase inhibitors to be combined with penicillinase sensitive PCN
1) clavulanic acid
2) tazobactam
3) sulbactam
Cephalosporins mechanism of action
Same as PCN, bind PBP’s and disrupt cell wall synthesis and activate autolysins
How has resistance against cephilosporins developed?
B-lactamases, altered PBP production with lower affinity
Cephalexin spectrum
Highly active against gram + bacteria, not a lot against gram -
5 generations of cephalosportins
1) cephalexin
2) cefoxitin
3) ceftazidime
4) cefipime
5) ceftaroline
Cefoxitin spectrum
Highly active against gram +, more active against gram - as well such as klebsiella
Ceftazidime spectrum
Highly active against gram + and neg, and pseudomonas, can penetrate CSF (DOC for meningitis)
Cefipime spectrum
Broad spectrum, high resistance to B-lactamases
Ceftaroline spectrum
MRSA mother fucker
Cephalosporin ADRs
- Allergic reaction
- cross reactivity with penicillin
- Reduction of prothrombin levels
- alcohol intolerance
- Ca2+ precipitate formation
Cephalosporins are ineffective against this type of bacteria
Enterococci
Carbapenems mechanism of action
-Bind PBP 1 and 2 cause weakening of bacterial cell wall with lysis and death, resistant to most B lactamases and can penetrate gram neg envelope
Imipenem spectrum
Very broad, many mixed infections with anaerobes, staph aureus, and gram neg bacilli, gram + and -, P. aeruginosa, B. fragilis
Cilistatin interacts with what drug to inhibit destruction by renal enzymes?
Imipenem
Imipenem ADR
- Siezures in elderly
- Cross allergy with penicillin
Meropenem spectrum
Active against most gram pos and gram neg, meningitis in children
Ertapenem spectrum
Narrower than other carbapenems, no activity against P. aeruginosa
Carbapenams absorption
Typically parenterally (IV)
Dorpipenim spectrum
Broad range, including P. aeruginosa
Aztreonam mechanism of action
Interferes with PBP3 to prevent synthesis of bacterial cell wall
Aztreonam spectrum
Narrow, only aerobic gram neg including
- H. influenzae
- P. aeruginosa
- Enterbacteriacieae
Types of infeections aztreonam treats
As a sub for aminoglycosides in UTI, lower respiratory, and soft tissue infections
Aztreonam ADR
Pseudomembranous colitis suprainfection
Vancomycin mechanism of action
-Inhibiting cell wall synthesis without PBP interaction
Vancomycin treats what organisms
- DOC for Cdiff, MRSA
- Serious infections in patients with PCN allergies
- Mostly gram pos
Vancomycin ADRs
Renal failure, ototoxicity, red man syndrome
Vancomycin absorption
Parenterally, IV
Teicoplanin
Similar action and structure to vancomycin, but largely devoid of any ADRs
Fosfomycin
Similar action and structure to vancomyscin, often used in uncomplicated UTI
Telavancin
Similar action and structure to vancomycin, treats complex skin infections and causes taste disturbance and foamy urine
Aminoglycoside spectrum
Narrow, only gram - aerobic bacilli, such as the enterobacteriaciae class
Aminoglycoside common ADR’s
Kidney and inner ear damage, neuromuscular blockage
Aminoglycoside mechanism of action
Dirsupt bacterial protein synthesis by binding 30 s ribosomal unit after active transport across cell membrane via Oxygen dependant process
Aminoglycosides, despite their status as a protein inhibitor, are fundamentally bacterio….
…cidal
Aminoglycoside resistance
Transfer of enzymes that inactivate them via R factors
Aminoglycoside absorption
Parenteral therapy or topical use
Gentamicin indication
Often used in combination with vanco or cephalosporin for severe gram + infection
Tobramycin indication
More active against P. aeruginosa, topical eye treatment
Amikacin 2 outstanding features
1) Broadest spectrum of all aminoglycocides
2) Least vulnurable to inactivation by bacterial enzymes
Neomycin 3 outstanding features
1) most toxic of all aminoglycosides
2) topical application
3) used to suppress bowel flora prior to surgery
