Pharm Week 3 Flashcards
How are antimicrobials different from other classes of drugs
The exert their action on bacteria infecting the host not the host itself
How can you prevent resistance
Dual therapy= using two drugs with different mechanisms of action
Ex: TB, pseudomonas aeruginosa, and enterococcal endocarditis
Things to avoid when prescribing antimicrobials
- misuse of anitbiotics
- overuse of broad spectrum antibiotics
- suprainfection (alterations of normal flora= yeast infection from too strong of an antibiotic)
Should you leave colonized flora in tact?
Yes
Pathogen
Organism causing active infection
Normal flora
Organisms normally found on the host: non pathogenic
Colonization
Presence of bacteria that are not causing disease
Do you culture otitis media, sinus infection, or UTI in otherwise healthy patients?
NO
How do you select your appropriate antimicrobial
- Spectrum of activity
- Effects on non-targeted microbial flora
- Appropriate dose
- Pharmacokinetic and pharmacodynamic properties
- ADR’s
- Drug interactions
- Cost
What is Empirical Therapy
An educated guess based on patient and antimicrobial specific factors: anatomical location, pathogens associated with presentation, potential for ADR’s, and antimicrobial spectrum of activity
What are patient specific considerations in antimicrobial selections?
- Recent previous antimicrobial exposure
- anatomical location
- Hx of drug allergies
- Organ dysfunction affecting drug clearance
- Immunosuppression
- Pregnancy
- Compliance
De-escalation
If you’re using a broad spectrum antimicrobial and you ID the pathogen with culture results, you narrow your antibiotic to something sensitive to the pathogen
What causes antimicrobial failure?
- Inadequate diagnosis
- Poor source control (removing catheters or draining an abscess)
- Development of new infection with resistant organism
- Non adherence
- Insufficient dosing
- Drug interactions
- Suprainfections
MIC
Minimal Inhibitory Concentration: you have to be above the MIC to effectively kill the pathogen
Gram positive
Has a cell wall and cell membrane, will hold the purple stain
Gram Negative
Has cell wall, cell membrane, and outer envelope which inhibits pink stain from sticking
Atypical
Possess uncommon qualities, colorless after staining, not a typical cell wall, can replicate, they ARE common
Anaerobic
Do not require O2 to live
What are the types of bacterial classification?
Gram Positive
Gram Negative
Anaerobic
Atypical
B-Lactam Antibiotics
Selectively interfere with the synthesis of the peptidoglycan bacterial cell wall. They are divided based on chemical structure and spectrum of activity
Why do you dose antimicrobials around the clock? q4h
antibiotics work best if the drug dosing trough concentration remains above the MIC throughout the entire dosing interval
Penicillin
Founded by Alexander Flemming on accident in 1929. It is the least toxic drug known, members of the family differ by a single side chain (R group)
Penicillin mechanism of action
interfere with bacterial wall synthesis by binding to PBP’s (penicillin binding proteins) disrupting the peptidoglycan layer
Penicillin therapeutic uses
treatment for bacterial pathogens
Natural Penicillins
Penicillin G aqueous- INJ
Penicillin G procaine and benzathine- IM only
Penicillin V (PenVeeK, Vi-CillinK)- PO
Penicillin G Aqueous- INJ
Natural Penicillin
Penicillin G Procaine and Benzathine- IM only
Natural Penicillin
Penicillin V (PenVeeK, Vi-CillinK) PO
Natural Penicillin
Amino Penicillins
Amoxicillin (Amoxil)- PO
Ampicillin (Omipen)- INJ, PO
Amoxicillin (Amoxil) PO
Amino Penicillin
Ampicillin (Omipen) INJ, PO
Amino Penicillin
Antistaphylococcal Penicillins
Dicloxacillin (Dynapen)- PO
Nafcillin (Nafcil, Unipen)- INJ
Oxacillin (Prostaphlin)- INH, PO
Dicloxacillin (Dynapen) PO
Antistaphylococcal penicillins
Nafcillin (Nafcil, Unipen) INJ
Antistaphylococcal penicillin
Oxacillin (Prostaphlin) INJ, PO
Antistaphylococcal penicillin
Antipseudomonal Penicillins
Piperacillin (Piperacil) INJ
Ticarcillin (Ticar) INJ
Piperacillin (Piperacil) INJ
Antipseudomonal Penicillin
Ticarcillin (Ticar) INJ
Antipseudomonal penicillin
B-Lactamase Inhibitor Combos (extended spectrum)
Ampicillin/Sulbactam (Unasyn)- INJ
Amoxicillin/clavulanate (Augmentin)- PO
Piperacillin/Tazobactam (Zosyn)- INJ
Ticarcillin/clavulanate (Timentin)- INJ
Ampicillin/Sulbactam (Unasym) INJ
B-Lactamase Inhibitor Combos (extended spectrum)
Amoxcillin/clavulanate (Augmentin) PO
B-Lactamase inhibitor combos (extended spectrum)
Piperacillin/tazobactam (Zosyn) INJ
B-Lactamase inhibitor combos (extended spectrum)
Ticarcillin/Clavulanate (Timentin) INJ
B-Lactamase inhibitor combos (extended spectrum)
What are the types of Penicillins
Natural Amino Antistaphylococcal Antipseudomonal B-Lacatamse inhibitor combos
Name the types of Cephalosporins
1st, 2nd, 3rd, 4th generation
Cefadroxil (Duricef) PO
1st generation cephalosporins
1st generation cephalosporins
Cefadroxil (Duricef) PO
Cefazolin (Ancef, Kefzol) INJ
Cephalexin (Keflex) PO
Cefazolin (Ancef Kefzol) INJ
1st generation cephalosporins
cephalexin (Keflex) PO
1st generation cephalosporins
2nd Generation cephalosporins
Cefaclor (Ceclor) PO Cefotetan (Cefotan) IV Cefoxitin (Mefoxin) IV Cefprozil (Cefzil) PO Cefuroxime (Zinacef) INJ Cefuroxime axetil (Ceftin) PO
2nd Generation cephalosporins
Cefaclor (Ceclor) PO Cefotetan (Cefotan) IV Cefoxitin (Mefoxin) IV Cefprozil (Cefzil) PO Cefuroxime (Zinacef) INJ Cefuroxime axetil (Ceftin) PO
Cefprozil (Cefzil) PO
2nd Generation cephalosporins
Cefuroxime axetil (Ceftin) PO
2nd Generation cephalosporins
3rd Generation Cephalosporins
Cefdinir (Omnicef) PO Cefditoren (Spectracef) PO Cefixime (Suprax) PO Cefotaxime (Claforan) INJ Cefpodoxime (Vantin) PO Ceftazidime (Fortaz) INJ Cefibuten (Cedax) PO Ceftriaxone (Rocephin) INJ
Cefdinir (Omnicef) PO
3rd Generation Cephalosporins
Cefditoren (Spectracef) PO
3rd Generation Cephalosporins
Cefixime (Suprax) PO
3rd Generation Cephalosporins
Cefpodoxime (Vantin) PO
3rd Generation Cephalosporins
Cefibuten (Cedax) PO
3rd Generation Cephalosporins
Cefotaxime (Claforan) INJ
3rd Generation Cephalosporins
Ceftazidime (Fortaz) INJ
3rd Generation Cephalosporins
Ceftriaxone (Rocephin) INJ
3rd Generation Cephalosporins
Cefuroxime (Zinacef) INJ
2nd Generation Cephalosporins
4th Generation Cephalosporins
Cefepime (Maxipime) INJ
Penicillin Mechanisms of Resistance
- B-lactamase/penicillinase: inactivate the drug’s B-Lactim ring
- Modified PBPs: Decreased affinity for the penicillins
- Decreased Permeability: gm-neg with modified external surfaces reduce drug permeability
What kills mostly gram-positive cocci, strep viridans, strep pyogenes? Treats syphillis, endocarditis, Strep. pneumonia, strep throat, group B strep infections
Natural Penicillins!!!!!
What treats otitis media & sinusitis (H. influenzae, Strep. pneumoniae) and simple UTIs?
Amino Penicillins!!!!
Why is amoxicillin preferred to ampicillin?
Better absorption and less diarrhea
-Ampicillin is just Amoxicillin dissolved in water.
What treats in any type of infection with documented pseudomonas aeruginose, serratia, of klebsiella (nosocomila pneumonia or UTI, complicated cellulitis, or abdominal infections
Antipseudomonal Penicillins!!!
If you add a B-Lactamase inhibitor to an penicillin what will it do?
Enhance the gram negative and anaerobic coverage of the original antibiotic making it broad spectrum coverage
What are B-Lactamase inhibitor combinations useful for?
Anaerobic infections or polymicrobial infections such as abscess, diabetic foot, abdominal infections, animal bites, fever of unknown origin, and sometimes refractory sinusitis/otitis media
Stink places: mouth, feet, and gut
Anaerobes
What do antistaphylococcal penicillins treat?
Staph. aureus and other gram positive cocci
-useful in soft tissue and bone infections, endocarditis
Cephalosporin
- same mechanism as penicillins (attacking bacterial cell wall)
- same mechanism of resistance (tend to be more resistant to B-Lactamase)
Cefotetan (Cefotan) IV
2nd Generation Cephalosporins
Cefoxitin (Mefoxin) IV
2nd Generation Cephalosporins
What are some classes of antibiotics that have the mechanism of action: inhibits bacterial ribosomal protein synthesis?
Tetracyclines
Clindamycin(Cleocin)
Macrolides
What are the three MACROLIDES?
clarithromycin (Biaxin) -PO
azithromycin (Z-pak, Zithromax) - PO,IV
erythromycin (multiple brands) -PO,IV, topical
What antibiotic class do these antibiotics fall into?
- clarithromycin (Biaxin)
- azithromycin (Z-pak, Zithromax)
- erythromycin (multiple brands)
Macrolides