BIIC Pharmacology Lecture 3_Antimicrobials 1 antibacterials Flashcards
What are the two bacterial enzymes associated with cell wall synthesis?
Transpeptidase and autolysin
What are three ways bacteria develop resistance to antibacterial medications?
1) Alteration of medications binding target (example PBPs)
2) Expression of efflux pumps
3) Degrading enzymes (example Beta Lactamase)
What are the common beta lactamase inhibitors?
Clavulanic Acid, sulbactam, tazobactam, avibactam
How are beta lactamase inhibitors used clinically?
They are coadministered with beta latam antibacterials to improve efficacy
What are the 4 main sub catagories of Penicillins?
1) Natural penicillins (penicillin G, penicillin V)
2) Anti-staphylococcal penicillins (oxacillin, dicloxacillin, nafcillin, methicillin)
3) Aminopenicillins (ampicillin, amoxicillin)
4) Antipseudomonal penicillins (piperacillin, ticarcillin)
NOTE: Both 3 and 4 are extended spectrum penicillins
What 5 things can natural penicillin often treat?
1) Pneumococcal infections (Streptococcus pneumoniae):
2) Gonorrhea (Neisseria sp.)
3) Gas gangrene (Clostridium perfringens)
4) Syphilis (Treponema pallidum)
5) Pharyngitis (ß-hemolytic streptococcus)
What are the two important Natural penicillins and how are they administered?
Penicillin G (IV or IM) Penicillin V (oral)
NOTE: Penicillin G is stabilized by benathine for IM repository injections. Also, penicillin is renally eliminated and has a short half life)
What are the 5 typical ADRs for Penicillin?
1) Hypersensitivity
2) Diarrhea (because of disruption to gut flora)
3) Acute Nephritis
4) Contraindicated in epilepsy
5) Decreased coagulation and cytopenia with prolonged use
What are the three main Anti-staphylococcal (Penicillinase resistant) penicillins
1) Nafcillin (IV)
2) Oxacillin (IV)
3) Dicloxacillin (PO)
What are the three things Anti-staphylococcal (Penicillinase resistant) penicillins are used to treat?
MSSA, Penicillin-susceptible Streptococci, Pneumococci
How is nafcillin eliminated from the body?
Biliary excretion
What are the two main Aminopenicillins?
Ampicillin (IV) - coadminister sulbactam
Amoxicillin (PO) - coadminister clavulanate
What can aminopenicillins be used to treat?
Most gram positive bacteria and some gram negative
NOTE: Amoxicillin is the drug of choice for URI
What is the only antipseudomonal penicillin? What can it be used to treat?
Piperacillin (IV/IM) - coadminister tazobactam
Effective against many gram negative bacteria including Pseudomonas, Klebsiella pneumoniae
What are sephalosporins and what are they good for?
- Cephalosporins are ß-lactam drugs
2. Penicillinase resistant (not resistant to cephalosporinase)
What are the two main first generation cephalisporins?
Cefazolin (IV) - cant penitrate BBB
Cephalexin (PO)
What can first generation cephalisporins be used to treat?
MSSA, streptococcal, and other penicillinase-producing staphylococcal strains (not MRSA)
What is the drug of choice for surgical prophylaxis and staph bacteremia?
Cefazoline
What are the three main second generation cephalosporins?
Cefaclor (PO)
Cefuroxime (PO)
Cefoxitin (IV)
What are second generation cephalosporins used to treat?
They have about the some coverage as first generation but with increased efficacy against gram negative bacteria.
What are the three main thrid generation cephalosporins?
Cefotaxime (IV, IM)
Ceftazidime (IV, IM)
Ceftriaxone (IV, IM)
What can thrid generation cephalosporins be used to treat?
Most drug resistant gram negative bacteria including Haemophilus and Neisseria Gonorrhoeae. Also third gen penitrates the BBB and can be used to treat menigitis
How is Ceftriaxone eliminated from the body?
Biliary excretion
What is the forth generation cephalosporin?
Cefepime (IV)
