22 Midterm 2 Review Questions Flashcards
Which antibiotics are Pregnancy Category B?
All Beta-Lactams, Synercid, Daptomycin, Clarithromycin, Azithromycin, Clindamycin, Flagyl (avoid 1st trimester), Nitrofurantoin (avoid at time of gestation), TMP/SMX (avoid in 1st and 3rd trimester)
Which antibiotics are Oral only?
Amoxicillin, Augmentin, Clarithromycin, Nitrofurantoin
Which antibiotics are IV only?
Unasyn (A/S), Oxacillin, Pip-Tazo, all CEPHs (except cefuroxime), all carbapenems, Synercid, Daptomycin, Telavancin, Aminoglycosides (Gent/Tobra), Tigecycline, Clindamycin
Which antibiotics have a Type I PD?
Aminoglycosides, FQs
Which antibiotics have a Type II PD?
All Beta-Lactams, Linezolid, Clarithromycin
Which antibiotics have a Type III PD?
Vancomycin, Synercid, Azithromycin, Doxycycline, Clindamycin
Which Beta-Lactams require no renal adjustment?
Oxacillin, Nafcillin, Ceftriaxone
What prophylaxis are Natural PCNs used for?
Rheumatic fever
What is the DOC for Treponema (syphilis)?
Benzathine Pen G
What is the DOC for Clostridia (Gas Gangrene)?
Natural PCNs
What is Oxacillin often used for?
Staphylococci
What is Amoxicillin often used for?
Endocarditis, prophylaxis for patient undergoing dental procedures
What is the only PCN derivative to cover Pseudomonas?
Pip/Tazo
Which CEPH covers B. fragilis, and therefore is good for surgical prophylaxis (colorectal)/intraabdominal?
Cefoxitin
Which Carbapenems have adequate CSF penetration with inflamed meninges?
Imipenem and Meropenem only
At what point do Carbapenems need renal adjustment?
All: CrCl < 10-20. Doripenem: CrCl < 50
What is the MOA of FQs?
Exerts antibiotic effect through inhibiting DNA synthesis –> inhibits bacterial topoisomerase II (DNA Gyrase) and topoisomerase IV
What is the MOR for FQs?
1) Target site mutation (gram (+); topo IV (parC, parE)). 2) Increased drug efflux (gram (-); OprM, MexA, MexB)
What is the PD of FQs?
Concentration dependent. Bactericidal
Which FQ doesn’t require renal adjustment?
Moxifloxacin
Most FQs are QD dosing, which one required BID?
Ciprofloxacin
What are some notable ADRs associated with FQs?
Cartilage toxicity. Photosensitivity
What are some notable DDIs associated wtih FQs?
ALL FQ agents interact with multivalent cations (chelation reactions can result in forming insoluble, inactive complex). Levo, Gati, Moxi - avoid QT prolongation drugs (erythro, antipsychotics, TCA)
What is some patient counseling for FQs?
May get drowsy, dizzy. Avoid/minimal caffeine. Separate antacids by 4 hours. Keep out of sun
What is the MOA of Bactrim?
Sulfonamide inhibits dihydropteroate synthetase. Trimethoprim inhibits dihydrofolate reductase
How does E. coli develop resistance to Bactrim?
Alteration to dihydropteroate synthetase –> lower affinity for sulfonamide
How does N. gonorrhoeae, S. aureus develop resistance to Bactrim?
Increase production of essential metabolite or drug (i.e. Increase PABA)
What is renal adjustment like for Bactrim?
Adjust when < 30 by increasing interval
What is Bactrim the DOC for?
Pneumocystis carinii
What are some serious ADRs associated with Bactrim?
Erythema multiforme, SJS, TEN
What needs to be monitored while on Bactrim?
Fluid status, CBC to f/u blood dyscrasias
What are some notable ADRs associated with Nitrofurantoin?
Peripheral neuropathy (w/ long term use). Respiratory
What are some precautions before Nitrofurantoin use?
Lung disease. Peripheral neuropathy. G6PD
What are contraindications to Nitrofurantoin use?
CrCl < 40. Pregnancy at term. Infants < 1 month
What is some patient counseling for Nitrofurantoin?
May cause GI upset, take with food or milk. May cause brown urine
What is the MOA of Metronidazole?
Enter cell, reductive activation
What are some notable ADRs with Metronidazole?
Nausea, abdominal pain. Metallic taste. CNS
What is some patient counseling for Metronidazole?
Can take w/ food to decrease stomach upset. Do not drink alcohol (including cough/cold) d/t disulfuram-like reaction. Metallic taste perverse
What is the MOA of Macrolides?
Reversibly bind to 23S ribosomal RNA in the 50S subunit of the bacterial ribosome. Interferes w/ peptide bond formation of growing peptide chain –> suppress RNA dependent protein synthesis
What is the MOR against Macrolides?
Target site alteration (ermA, B, C). Alteration in transport (efflux): mrsA, mefA, mefE
What are the class effects for PK of Macrolides?
Lipophilic, extensive tissue/fluid penetration. Respiratory concentration > serum
What is the PD of Macrolides like?
Bacteriostatic. Time dependent
Which Macrolide requires renal adjustment?
Clarithromycin
What are the clinical applications of Erythromycin?
Motilin effect. Diabetic gastroparesis. Post op ileus
What is a notable ADR associated with Clarithromycin?
Taste perversion (metallic)
What is a rare effect that Macrolides have?
Immunomodulatory effects
What class of antibiotic is Telithromycin?
Ketolide
What is Telithromycin designed to do?
Treat macrolide-resistant respiratory tract infection
What are some notable ADRs of Telithromycin?
Hepatotoxicity, QT prolongation, NV
Which antibiotics are strong inhibitors of CYP3A4?
Macrolides (not azithro). Telithromycin, Synercid, Metronidazole
What does Clindamycin not get to?
CSF
What is a notable ADR with Clindamycin?
Increased LFTs
Which Tetracyclines require renal adjustment?
Tetracycline. Minocycline
What is the MOA of Tetracyclines?
Reversible bind to 30S ribosome, inhibits binding of aminoacyl-tRNA to acceptor site on 70S ribosome
What is the PD of Tetracyclines?
Bacteriostatic. Time dependent
Which Tetracycline doesn’t require renal adjustment?
Doxycycline
Which Tetracycline is PO only?
Tetracycline
What are some notable ADRs associated with Tetracyclines?
Photosensitivity. Tooth discoloration. Inhibition of growth and bone deformities
What are some additional ADRs only seen in Minocycline?
Vertigo. Drug induced lupus
What are some counseling points for Tetracyclines?
Separate dose from milk, antacids, iron supplements by > 2 hours
Does does Tigecyline not cover?
No coverage of the Big 3P: Pseudomonas, Proteus, Providencia
What are the clinical applications of Tigecycline?
Complicated skin and skin structure (cSSSi). Complicated intraabdominal infections (cIAi)
What are the common ADRs of Tigecycline?
N/V/D
Why is Tigecycline not used anymore?
Increased risk of mortality from post market data
What is the MOA of Quinupristin/Dalfopristin?
Inhibits protein synthesis. Dalfo alters ribosomal conformation, increasing affinity for quinu
What is the PD of Synercid?
Bactericidal except E. faecium (static)
What is a notable ADR associated with Synercid?
Arthraigia, myalgia: may require analgesics for pain control, and extend dose to Q8 - Q12
What is the MOA of Linezolid?
Attacks at pre-initiation (unique)
What is the PD of Linezolid?
Bacteriastatic against most, cidal against some pneumococcis. Concentration independent
What are the clinical applications of Linezolid?
Vanco-R Enterococci infection. MRSA infection (d/t intolerance to vanco or vanco failure)
What are the big ADRs associated with Linezolid?
Thrombocytopenia, Anemia, Leucopenia. Increased risk with duration > 2 weeks. Monitor CBC weekly
What is a notable DDI with Linezolid?
Serotonin syndrome when used with SSRIs
What is the MOA of Daptomycin?
Binds to bacterial cell membrane, calcium dependent, insertion of lipid tail. Rapidly depolarizes cell –> cell death
What is the PD of Daptomycin?
Concentration dependent killing. Bactericidal
What are some notable ADRs with Daptomycin?
CPK elevations (monitor weekly), look out for muscle pain, weakness, distal extremities
What is Daptomycins place in therapy?
Only for treatment of cSSSi caused by susceptible organisms and bloodstream infection cause by S. aureus
