Card Set Information
HUSOP DA EXAM1 Penicillins
Questions from the Penicillin lecture
The main mechanism of action of penicillins is __________.
Interfering with bacterial cell wall synthesis
What does the variable side chain of penicillins dictate?
Antibacterial and pharmacological characteristics.
The _________ is the highly reactive 3-carbon, nitrogen part of a penicillin.
Beta-lactam ring or center
Penicillins inhibit ____________.
What is the role/function of transpeptidase?
It cross links peptides found in the peptidoglycan cell wall, connecting parallel chains.
As cross linking of peptides is inhibited, the bacteria_____________
Cell wall weakens, and the cell dies.
By what two mechanisms may bacteria be killed? Describe each one.
Lytic and non-lytic. Lytic involves membrane rupture and non-lytic involves loss of membrane potential.
Penicillin __________ binds ___________resulting a number of different outcomes depending which ________ bound.
Name and describe the three mechanisms by which penicillin resistance occurs.
Decreased affinity of PBP's for B-lactams, inability of B-lactams to access site of action, and enzymatic degradation
What is the enzyme that degrades B-lactams?
Gram positive tend to have _______ penicillinases, but gram negative bacteria _________.
More, have effective penicillinases due to their location
Where are genes for B-lactamases found?
Chromosome or plasmid and can be transferred
What is the most common adverse effect associated with penicillins?
Immediate immune reactions to penicillin is ______ mediated whereas later reactions are ______ mediated.
IgE, IgG or IgM
Fatalities involving ______________ have occurred with low doses or even skin testing with penicillin.
Name five other adverse reactions to penicillin.
Maculopapular rash, uticarial rash (hives), fever, bronchospasm, vasculitis, serum sickness, exfoliative dermatitis, Stevens-Johnson syndrome, acute anaphylaxis, angioedema, and contact dermatitis
Name three less commmon adverse reactions to penicillin. What may these depend on?
Seizures, bone marrow depression, granulocytopenia, diarrhea, nausea & vomiting, and injection site pain or inflammation.
Pencillin G has ______ oral absorption, while V has _______ oral absorption.
Poor (varied), good
Do penicillins V & G have resistance to penicillinase?
Pen V & G have good activity against ____________ and most _______________.
Treponema pallidum, streptococci
Pen V & G have moderate activity against ____________ and _______________.
Streptococcus pneumoniae, enterococci
Penicillin-resistant penicillins are also called what?
Oxacillin and dicloxacin are what type of penicillin? What are their oral absorptions?
Antistaphylococcal penicillins, good
Nafcillin is what type of penicillin? What is its oral absorption?
Antistaphylococcal penicillin, variable
Penicillin-resistant penicillins have good activity against __________ & __________.
Methicillin-sensitive staph. Areus, streptococci
Penicillin-resistant penicillins have poor activity against __________ , __________,__________, & ___________
Gram-negative rods, enterococci, anaerobes, MRSA
Penicillin-resistant penicillins are eliminated through the _________, so they are a good choice for patients with _____.
Liver, renal insufficiency
Two aminopenicillins are?
Ampicillin & amoxicillin
Do aminopenicillins have good oral absorption?
Yes, amoxicillin has excellent oral absorption
The aminopenicillin specrum includes ________ & __________
Gram positive, gram negative
Aminopenicillins have good activity against which of the following?
a. staphylococci b. streptococci c. enterococci d.anaerobes e. B & C f. all of the above
Aminopenicillins have poor activity against ________ & _________
Ticarcillin and piperacillin are ________________ penicillins.
Antipseudomonal penicillins are given by which route?
Piperacillin extends the spectrum of __________ to include ____________
Activity of ticarcillin is _________ to that of __________
Piperacillin has activity against __________ & _________, but may encounter reistance because of __________.
Enterobacteriacae, bacteroides, B-lactamase