Drugs for PNA Flashcards
The fluoroquinolone, Ciprofloxacin, inhibiys what enzyme?
DNA Gyrase
important in killing Gram - bacteria (pseudomonas)
Fluoroquinolones that block Topo IV is important for killing which type of organisms?
Gram +
(streptococcus respt. infections)
Are fluoroquinolones a first choice drug or a last resort drug for CAP?
Last resort for CAP
Should penicillins and aminoglycosides be combined in the same IV?
NO!
What is the MOA of Amoxicilin?
What step of peptidoglycan synthesis is inhibited?
Is it effective against G+ and G-?
inhibits bacterial cell wall synthesis by binding to PBP
the final transpeptidation step is inhibited
Yes
Does Amoxicillin +/- Clavulanate kill Pseuodomonas?
What is this combination used for?
No!
CAP
what are the main adverse effects of Amoxicillin +/- Clavulanate?
Anaphylactic Rxn
C. Diff
In Mono-rash
What is the MOA of Piperacillin?
What is the MOA of Tazobactam?
Is it active against Pseudomonas?
inhibits bacterial cell wall synthesis
Inhibits beta-lactamases
Yes!
Piperacillin + Tazobactam kill which types of pathogens?
Gram + and Gram - aerobic and anaerobic, including those who produce beta-lactamases
What are the main indications for Piperacillin + Tazobactam?
CAP and HAP/VAP
What is the benefit of using Ceftriaxone in patients with kidney diseases?
It is not eliminated by the kidney, so the dose does not need to be adjusted for renal impairment
What class of drugs can cause bleeding tendencies?
Cephalosporins
(cefmetazole, cefoperazone, cefotetan, ceftriaxone)
What are the third and fourth generation parenteral cephalosporins?
Ceftriaxone (3rd)
Cefepime (4th)
What are the third generation oral cephalosporins
Cefditoren
Cefpodoxime-Proxetil
What are the clinical applications for Cefpodoxime?
COPD
OM
CAP outpatient tx
What are the clinical applications for Cefditoren?
exerbation of chonric bronchitis
CAP
pharyngitis
Are Cefpodoxime and Cefditoren orally active?
What is the 1/2 life?
Are there any drug-drug interactions?
Yes
2-3 hours and 1.6hrs, increased with worsening renal function
Yes
What are some concerning adverse effects of Cefpodoxime and Cefditoren?
B-lactam allergies
Superinfection (C.diff)
Which drug class is bacteriostatic at the 30S subunit ?
Tetracyclines
Kills bacteria that lack cell walls (Mycoplasma pneumonia)
Which tetracycline is the drug of choice for CAP?
Doxycycline
Who should not receive Tetracyclines and why?
Don’t use in children due to risk of teeth staining
What things interfere with tetracycline absorption?
What is recommended to avoid GI upset?
Should it be combined with bactericidal drugs (PNC)?
Antacids (Aluminum, Ca, Mg, Fe) and dairy products
Take with water
No, generally not recommended
Which drug class binds to the 50S subunit and blocks elongation and is BacterioStatic ?
Macrolides (Erythromycin)
What are the macrolide drug of choice for CAP?
Azithromycin
Clarithromycin
Macrolides are effective against which bugs?
Most Aerobic and anaerobic gram + bugs
Not Gram negatives except: Pasturella, Haemophilus, Neisseria
Legionella, Mycoplasma, mycobacteria, rickettsia, chlamydia
No fungi
Which drug is a well knwon inhibitor of cytochrome P450?
Erythromycin
increases concentration of other drugs
Which drug causes less GI upset, erythromycin or clarithromycin?
Clarithromycin causes LESS GI upset
Unlike Erythromycin, which macrolide does NOT disrupt CP450?
Azithromycin
concentrates in cells and slowly releases bacteriostatic levels over 2-4 days (1/2 life)
Which drug class is broad-spectrum, administered orally, and is more effective than tetracyclines or macrolides for PNA?
Fluoroquinolones (-Oxacins)
Use as LAST RESORT to minimize tolerance
What is the main adverse effect of Fluoroquinolones?
Tendon rupture, especially Achille’s Tendon in elderly, children, and those at risk
What are the indications for Vancomycin?
What can infusing too fast cause?
MRSA, MRSE, serious allergy to PNC
C. diff
Red Man Syndrome
Which drug binds to ribosomal A to prevent tRNA binding, thus inhibiting the first step of protein synthesis
Linozolid
What are the clinical applications of Linezolid?
VRE
CAP (methicillin susceptible) and HAP (methicillin-susceptible and resistant)
Linezolid can be administered which two ways?
It inhibits which important enzyme, leading to which side effects?
Oral and IV
MAO–> neurologic sx, serotonin syndrome
What is the MOA of Aztreonam?
What is it effective against?
inhibits bacterial cell wall synthesis by binding to PBP
Gram -, including Pseudomonas
No use against Gram + or anearobes
What is the MOA of Imipenem?
What is it effective against?
inhibits bacterial cell wall synthesis by binding to PBP
Wide spectrum of G+ and G-, aerobes and anaerobes, many MDR strains
What is the main clinical application of Imipenem?
lower respiratory tract infections
Gentamicin binds to which ribosomal subunit thus inhibiting growth?
What is Gentamicin used for?
30S subunit
Respiratory tract infections?
What are the main toxicities of Gentamicin?
Nephrotoxicity
Neurotoxicity
Ototoxicity
What drug used to be the drug of choice for aspiration PNA but now is associated with C. diff?
Clindamycin
What bugs undergo post-translational modifications that give rise to antibiotic resistance?
(mnemonic)
ESKAPE
E. Coli
Staphylococcus
Klebsiella
Acinetobacter
Pseudomonas
Enteroccocus
