beta Lactams Flashcards
What anti-staphylococcal drug should you never choose on a clinical stem because it is not used?
Methicillin
What beta lactamase inhibitor is used with the extended spectrum drug, AMPICILLIN?
Route?
sulbactam
IV
What beta lactamase inhibitor is used with the extended spectrum drug, AMOXICILLIN?
route?
Clavulanic acid
Oral
Anti-Psudomanal Drugs + their combo with a beta lactamase inhibito
- Ticarcillin + clavulanic acid
- Pipericillin + Tazobactam
What enzyme do penicillins block?
transpeptidases
complication of penecillins
hypersensitivity type 4/anaphylaxis
Drugs of choice for penicillin resistant but methicillin-sensitive organisms like S. aureus (MSSA)?
- Nafcillin
- Oxacillin
- Dicloxacillin
If Methicillin is given to a human what is the result
interstitial nephritis
Route of administration for Nafcillin?
IV so hospital setting
Route of administration for oxacillin and Dicloxacillin
oral so outpatient
What do Methicillin adn related anti-staphylococcal penicillins bind to
PBPs (penicillin binding proteins)
What gets altered in S. aureus to confer high level resistance to Methicillin . .. MRSA
MecA gene and PBP2
What is given to treat MRSA?
vancomycin
What is given to someone who has severe allergic reaction to anti-staph drugs?
vancomycin
What type of bacteria do you use Vancymycin for?
Gram +
- MRSA
- MRSE
- enterococci
What can be used to treat C. Difficile if metronidazole fails
Vancomycin
Is vancomycin a substitute to treat MSSA if no known allergies to penicillin?
NO. antistaphylococcal drugs are superior
How does vancomycin and teicoplanin inhibit cell wall synthesis?
binding the D-ala-D-ala and sterically hindering TRANSGLYCOSYLATION and transpeptidation
Rate of Vancomycin and route?
parenteral and slow (60-90) min
Side effects that is exacerbated with other drugs that have same effects?
Nephro and oto toxicities
Adverse effects of Vancomycin?
- erythroderma/shock
- nephro/oto toxicity
- rash
- phlebitis at injection site
what drugs act by entering porins and binding to PBPs in the PERIPLASM to disrupt cell wall integrity
Extended spectrum penicillins
- Ampicillin
- Amoxicillin
What drugs are more soluble and can cover gram negatives
Extended spectrum penicillins
- Ampicillin
- Amoxicillin
What are the clinical indications for extended spectrum penicillins
- Respiratory infections (CAP, sinusitis, bronchitis, pharyngitis)
- Bronchitis from COPD
- Otitis media
What is often used for pharyngitis in children because of taste
Amoxicillin
Amoxicillin Absortption in gut approaches 100% which negates its use for what?
enteritis (shigella, salmonellla)
is Ampicillin and Amoxicillin active against MRSA and MRSE?
No
What situations are people at risk for pneuomonas infection?
- Burn
- CYSTIC FIBROSIS
- Injection drug users
- Immunosuppressed
Ticarcillin and piperacillin cover what?
- psuedomonas
- Gram negative rods (enterobacter spp., E. coli, Proteus mirabilis, Hemophilus influenza)
What is more potent between piperacillin and Ticarcillin
Piperacillin
Why do you pair and anti-pseudomonal drug with a Beta lactamase inhibitor?
For EMPIRICAL therapy
- Severe pneumonia in hospitalized patient with a structural disease (COPD)
- Aspiration pneumonia in hospitalized patients
- NEUTROPENIC FEVER
Stems that lead towards neutropenic fever and use of anti-pseudomonal drugs
- transplants
- lots of steroid
- cancer patient got chemo
Generations 1-3 cephalosporins lack activity against what organisms?
- Listeria monocytogenes
- Legionella
- Atypical mycoplasma
- MRSA
- Enterococci
1st gen cephalosporins
- Cefazolin
- CEPHALEXIN
- cephradrine
What 1st generation cephalosporin is oral only
cephalexin
What can 1st gen cephalosporin can be taken twice daily to treat pharyngitis
Cephalexin
What generation of cephalosporins is used for surgical prophylaxis if skin flora are likely pathogens; soft tissue and skin infections due to S. aureus and S. pyogenes
1st generation
What generation cephalopsporins are used for intra-abdominal and gynecological sepsis, surgical prophylaxis for intra-abdominal and colorectal surgery
2nd generation
2nd gen cephs
- cefoxitin
- cefotetan
- cefaclor
- cefuroxime axetil
3rd gen cephs
- ceftriaxone
- cefotaxime
- cetazidime
- cefaperazone
What 3RD gen ceph is particularly active against P. aeruginosa
Ceftazidime
What is the 4th gen ceph drug called that is pretty much equal to ceftazidime in treating P. aeruginosa?
Cefepime
Adverse effects of cephalosporins?
- Hypersensitivity
- Disulfiram-like reaction
if a patient has had a recent, severe hypersensitivity reaction to a penecillin, do you give a ceph?
no
What two cephs reduce vitamin K-producing bacteria in GI and cause hypoprothrombinemia and bleeding so should be used with caution in patients taking warfarin or with coagulation abnormalities
Cefotetan and cefaperazone
What is the one Monobactam?
Aztreonam
What do Monobactams treat?
Gram (-) rods
When do you used Aztreonam
substitute for extended spectrum penicillin or gen 3,4 cephs if these are contra-indicated because of hypersensitivity
What is the carbapenems, Imipenem always administered with and why?
Cilastatin because it causes nephrotoxicity
Adverse effects of Carbapenems?
- hypersensitivity and rash
- CNS toxicity: seizures and confusion
- Nephrotoxicity
what enzyme does cilastatin inhibit to prevent the nephrotoxicity caused by imipenem?
dipeptidase
